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Wiley Professional Digital Compositing: Essential Tools and Techniques

1. After Effects CS3 logo m Interview Richard Shackleton The Foundry London 37 LL There is a great deal of competition when it comes to compositing software How does After Effects differentiate itself from the pack MC After Effects is surprisingly easy to use and has a great deal of flexibility to handle a broad range of projects It integrates very well into broader workflows and it s almost guaranteed that the people you hire already know how to use it When it comes to other compositing products I think you ll find that After Effects is more of a complement than a competitor If you ask someone who owns another compositing product if they also use After Effects the answer is probably yes LL After Effects is layer based What is the greatest advantage of a layer based system when compared to a node based system MC Most people have a mental model of a composite that looks like a stack of layers The After Effects user interface is organized around a timeline that reflects the stacking order of the layers When animation and timing come into play the advantages of a layered timeline begin to shine After Effects has the best timeline in the industry and it s truly a joy to animate with it With After Effects CS4 we introduced a new feature called the mini flowchart that visualizes the nesting structure and makes navigating among composi tions much faster It s quite handy and provides some of the advantage
2. Output Module Settings Figure 1 18 The top of the Output Module Settings dialog box Interlacing in AE If you import interlaced video footage the interlacing is recognized and is indicated by the footage statistics provided at the top of the Project panel The word separating is included with an indication of which field is dominant upper or lower see Figure 1 19 An upper field contains the odd lines of a frame while the lower field contains the even lines of a frame Different video formats carry different field dominances which affect the way edits are made and how de interlacing is carried out When After Effects identifies interlacing it separates the fields and converts them to individual frames In essence this doubles the frame rate If you open the footage in the Footage panel you can examine each separated field by stepping through the Footage panel timeline with the Page Down and Page Up keys For example if the footage has lower dominance and the timeline is at frame 1 the lower field of frame 1 is displayed Pressing the Page Down key once displays the upper field of frame 1 Pressing the Page Down key a second time displays the lower field of frame 2 The frame num ber is indicated by the Footage panel s Current Time button If footage is field separated and dropped into a composi I tion only the dominant field of each frame is displayed by the S f Composition panel as you play the timeline see Fig
3. m Setting Up a Composite 15 A B C D E F G H 00001 29 97 fps ey Koa AHO A SYA G Soucename H NAHOOOD Paret IJ KL MNOPQRST Figure 1 12 Layer outline of Timeline panel The composition switches include A Open Parent B Live Update C Draft 3D D Hide Shy Layers E Frame Blending F Motion Blur G Brainstorm and H Graph Editor The layer switches include I Video J Audio K Solo L Lock M Shy N Collapse Transformations O Quality P Effect O Frame Blending R Motion Blur S Adjustment Layer and T 3D Layer Composition switches affect all the layers of a composition while layer switches affect individual layers Composition switches include the following Open Parent when clicked displays a menu that lists the nested location of the cur rent composition For example if Comp 1 is nested inside Comp 3 the menu reads Comp 3 Layer n If you select a menu item the Timeline panel will jump to the com position tab where the nesting occurs Live Update when toggled on updates the composition in the viewer while its layers are transformed or otherwise manipulated If Live Update is toggled off manipulated layers are drawn as wireframe boxes Draft 3D when toggled on disables 3D lights shadows and camera depth of field 3D setups are discussed in Chapter 11 Working with 2 5D and 3D Hide Shy Layers if toggled on hides all Shy layers see the list of layer switches later
4. Setting Up a Composite Education is important I think people need to make sure that they re learning to Fi be artists and not just learning tools ae GIANNI ALIoTTI lead lighter DreamWorks Animation Before beginning a composite its important to understand the fundamental differences between layer and node based compositing systems A strong knowledge of common image resolutions and frame rates will allow you to make correct decisions Once the fun damentals are grasped setting up a compositing project or script becomes fairly easy Since this book uses both After Effects and Nuke you will be required to learn two different workflows However if you master both you will be well suited for work in the feature animation visual effects and commercial production industries To add perspective to the lessons professional compositing examples are included In addition the first 3 of 19 interviews with professional compositing supervisors lead composi tors and compositing experts are added at the end of this chapter Two tutorials are also provided to get you started in After Effects and Nuke CHAPTER 1 m Setting Up a Composite Compositing Challenge Digital compositing is the process of digitally assembling multiple images or image sequences into a single piece of motion picture or digital video footage The goal of a successful digi tal composite is to make the source material appear as if it has always
5. Shy hides the layer if the Hide Shy Layers composition switch is toggled on If a layer is hidden it is no longer visible in the layer outline but it continues to influence the composite Collapse Transformations if toggled on preserves image integrity for nested compo sitions For example the following may occur 1 Layer A which is carried by Comp A is transformed 2 Comp A is nested within Comp B 3 Comp B is transformed 4 Asa result layer A is essentially transformed two times This double transforma tion can destroy pixels unless the transforms are collapsed and a net transfor mation is calculated at the start This process is known as concatenation which is discussed further in Chapter 5 For more information on nesting see the next section Quality toggles between a draft and best quality render A backward slash indicates draft while a forward slash indicates best quality Effect if toggled off disables any effects applied to the layer Adjustment Layer when toggled on converts the layer into an adjustment layer which automatically applies any effects it carries to all layers below it The RGB information of the layer itself is hidden By default the layer outline is set to display switches However you can toggle to the menu view by clicking the Toggle Switches Modes button at the bottom left of the Timeline panel The menu view includes Mode menu buttons which set each layer s blending mode and T
6. 6 The final composite combines the defocused city the CG pillar the fake window reflection the actress and the touched up table All the elements are color graded so that they work as a whole A glow is added to create light wrap along the edges of objects in front of the window Tonya Smay for Westchester Medical Center Figure 1 4 shows two shots composited by Tonya Smay in After Effects for the Westchester Medical Center Tonya works as a freelance compositor in the New York area To read an interview with Tonya Smay see Chapter 12 Advanced Techniques The breakdown 1s as follows 1 A CG render of a medical center grounds cre Figure 1 3 Six compositing steps used by AILV to create a ated in Maya is brought into the composite as spec commercial separate render passes The camera is moving during the shot The renders remain somewhat bare and are missing the sky 2 A camera is exported out of Maya and imported into After Effects In addition sev eral nulls indicating specific locations within the model are imported The composite is converted to a 3D environment Several 3D cards are set up with trees bushes water spray and a sky Because the composite uses a camera exported from the 3D program the cards motion follows the 3D render perfectly To prevent occlusion 6 CHAPTER 1 m Setting Up a Composite issues RGB ID render passes of the model are imported and are converted to holdout mattes ID passes of
7. Click the OK button In the Render Queue tab note the phrase Comp 1_ tga next to Output To This is the default name given to the soon to be rendered frames To change to a different render directory click the phrase Comp 1_ tga In the Output Movie To dialog box browse for a directory You can also type in a new render name in the File Name cell The portion of the name is critical for proper frame numbering Two pound signs indicate two numeric placeholders which is suitable for a timeline dura tion that runs between 10 and 99 frames Click the Save button to close the Output Movie To dialog box Click the Render button To examine the rendered footage import it into the project Choose File gt Import gt File In the Import File dialog box browse for the rendered footage Because it s an image sequence you need only select the first frame of the sequence The program automatically imports the entire sequence as a single unit Double click the new footage s name in the Project panel to open it in the Footage panel Step through the footage one frame at a time to examine the quality Since the footage was rendered without interlacing there are no fields Note how the footage progresses in coarser steps Every other field was lost during the render Nevertheless the footage is fairly high resolution so it still creates smooth motion The tutorial is complete A sample After Effects project is included as ael aep in the Tu
8. QuickTime or AVI by clicking the Render tab choosing an output tab in the Render dialog box and click ing the Render button You can load previously rendered sequences or movies by pressing the Desktop tab and browsing for files To add a file to the timeline press the sign that appears over the file icon Multiple movies and image sequences can exist on the timeline simultaneously Additional Resources FrameCycler Documentation FrameCycler is a robust player that includes support for basic editing color grading 3D LUTs version management network file sharing command line control and stereoscopic vision For documentation on the extensive interface and built in toolsets see the HTML Documentation Index in the FrameCyclerWindows doc folder located within the Nuke program directory Writing an Image Sequence To render a composite to disk create a Write node To do so select the node whose output you wish to render RMB click in the Node Graph and choose Image gt Write Browse for a location by clicking the browse button beside the File parameter in the Write node s properties panel see Figure 1 30 Add the filename to the path cell using the format name extension For example enter C render test tga if you are rendering between 100 and 999 frames Click the Save button The program automatically recognizes the filename extension and sets the File Type menu for you Each File Type setting adds a unique set of quality
9. To isolate particular layers for a render toggle off the Video layer switch for any layer that is unwanted Using Composition Footage and Layer Panels There are four types of panels that appear in the central section of the After Effects inter face Composition Footage Layer and Flowchart To see a particular composition in the Composition panel double click the composition name in the Project panel To view imported footage in the Footage panel double click the footage name in the Project panel To view a layer by itself in the Layer panel double click the layer name in the layer outline of the Timeline panel The Footage and Layer panel differs from the Composition panel in that they possess their own timelines If the Composition panel is open and you switch between composition tabs in the Timeline panel the active composition is automatically displayed The Composition Footage and Layer panels each carry their own viewer The viewer may show the default 2D view or carry multiple views of a 3D environment 3D envi ronments are described in Chapter 11 the Flowchart panel is discussed in the next section Aside from carrying viewers Composition Footage and Layer panels include a num ber of menus and controls see Figure 1 14 Figure 1 14 Composition panel switches and menus A Always Preview This View B Magnification Ratio Popup C Choose Grid And Guide Options D Toggle Mask And Shape Path Visibility E Current
10. better time based view useful when working with multiple shots together in a sequence LL Nuke has always operated in 32 bit floating point How would you summarize the advantages of floating point over lower fixed bit depths RS Even in 1993 floating point calculations were faster than integers on modern proces sors Floating point also offers a wider latitude which allows linear data representation rather than having gamma to encode detail in specific areas This allows artistic and tech nical freedom during image processing thereby removing the need to carefully manage clipping in the data For example this is useful in color correction where values are pushed up and down multiple times in succession with depth or motion data where great accuracy is needed and in HDR workflows that need to support a wide range of exposure values m Interview Richard Shackleton The Foundry London 39 LL Nuke is designed for a feature film production environment Do you consider the core client to be visual effects professionals RS The core client is visual effects professionals supporting artist and production needs in feature films commercials CG animation and high value television drama and documentaries
11. by arrows There are several advantages to layer based programs Layers are intuitive to use It s fairly easy to imag ine the result of dropping one layer on top of another particularly when the majority of digi tal artists are familiar with the Photoshop layer workflow You can quickly set up a simple composite utiliz ing a limited number of layers The same simple composite in a node based program can require additional steps For example Nuke may require the addition of a Bezier node whereas After Figure 1 6 A Nuke node network with five nodes The Effects automatically provides the Pen tool arrows of the connection lines pipes indicate the When layers are stacked they are merged auto direction information is flowing matically A node based program requires some type of merge node to supply the blending mathematics There are several advantages to node based programs You can use the output of one node as the input to numerous other nodes Although you can nest composites in a layer based program it becomes difficult to manage on complex projects Once you are familiar with a node based workflow complex node networks are easy to interpret Inputs and outputs in a node network are clearly indicated by node con nection lines With a complex layer based composite it becomes difficult to trace inputs and outputs because the main graphic representation only indicates position within a layer outline of a particular comp
12. can browse for the foot age by clicking the File browse button see Figure 1 22 Nuke automatically recognizes image sequences and represents them with the following syntax name padding extension Padding indicates the number of numeric placeholders used for the sequence numbering This is encoded as 01d 02d 03d and so on 02d for example signifies that there are two placeholders which creates 01 02 03 and so forth Extension is the three letter file format code such as tga 24 CHAPTER 1 m Setting Up a Composite Read Sequence Node file C Projects Chapter3 F ootage smoke smoke 2402d_tga format 1280x7207 proxy proxy format root proxy_format 640x480 frame range 1 hold 10 frame missing frames Emor reload colorspace default premultiphed raw data Figure 1 22 A Read node s properties panel Within the Read node s properties panel you can set the color space and alpha pre multiplication of the imported files These parameters are discussed in Chapter 2 and Chapter 3 If the resolution of imported footage does not match the Full Size Format setting in the Project Settings properties panel the footage will not fit the project resolution frame Thus it may be necessary to connect a Reformat node For a demonstration of this see the section Nuke Tutorial 1 Working with the Reformat Node at the end of this chapter Connecting Nodes You can connect nodes in an almost endless
13. footage and in Nuke you ll work with footage that has different resolutions AE Tutorial 1 Working with Interlaced Footage Working with interlaced video footage presents its own unique set of challenges 1 Open After Effects Choose File gt New gt New Project Choose File gt Project Settings In the Project Settings dialog box select the Frames radio button in the Display Style section This consecutively numbers frames on the timeline Note that the Project Settings dialog box includes Depth bit depth and Working Space color m Setting Up a Composite 31 space menus It s important to set these menus at the start of each project Chapter 2 discusses bit depths and color space in great detail For this tutorial Depth may be left at 8 Bits Per Channel and Working Space may be left set to None Click the OK button Choose Composition gt New Composition In the Composition Settings dialog box change the Preset menu to HDV HDTV 720 29 97 This sets the width to 1280 the height to 720 and the frame rate to 29 97 Change the Duration cell to 60 and click the OK button Comp 1 is added to the Project panel Choose File gt Import gt File In the Import File dialog box browse for interlaced mov in the Footage folder on the DVD interlaced mov is added to the Project panel LMB drag the QuickTime from the Project panel to the outline layer of the Comp 1 tab in the Timeline panel Play back the timeline The motion of
14. in this section Frame Blending if toggled on enables frame blending for all layers This is necessary for time warping which is described in Chapter 12 Advanced Techniques Motion Blur if toggled on enables motion blur for all layers and is described in Chapter 6 Convolution Filters Brainstorm if clicked creates multiple temporary variations of the composition To activate the Brainstorm dialog box you must first select layer properties The Brainstorm function randomly offsets the values of the selected properties to create the composite variations Graph Editor if toggled on reveals the Graph Editor in the Timeline panel For infor mation on the Graph Editor see Chapter 5 Transformations and Keyframing As for layer switches the Frame Blend switch is discussed in Chapter 12 the Motion Blur switch is covered in Chapter 6 and the 3D Layer switch is detailed in Chapter 11 Additional layer switches follow Video toggles the layer s visibility The layer remains in the layer outline but it is not used for the composite Audio mutes any audio attached to the layer Since this book is concerned with digital compositing the audio functionality of After Effects is not covered Solo displays the layer for which the switch is activated but disables all other layers 16 CHAPTER 1 m Setting Up a Composite Lock when toggle on prevents alteration of the layer s properties or transformations
15. interlacing but stretches the footage vertically by 125 A Transform node is added with its Scale property set to 1 0 75 A Reformat node is included so that the result of the Transform node is snapped back to the correct 1280x720 bounding box size In addition Nuke 5 1 includes two gizmo nodes for working with pulldowns Add 3 2 Pulldown and Remove 3 2 Pulldown Both are found in the Time menu Each me carries a Phase parameter which you can use to offset the sol EA fields incrementally Various interlacing deinterlacing plug de ae an ey y Various interlacing deinterlacing plug the Tutorials folder ins and gizmos are available for Nuke For example the onthe DVD FieldsKit gizmo is available at ww creativecrash com Figure 1 31 A Delnterlace node removes interlacing with the help of a Transform and Reformat node A sample Nuke Tips amp Tricks Nuke Primitives Nuke provides a number of primitives that are useful for testing networks or seeing the results of particular filters You can add a primitive to the Node Graph by RMB clicking and choos ing either Image gt node or Draw gt node The Image menu carries the Constant solid color Checkerboard and Colorbars NTSC test pattern nodes The Draw node includes the Radial solid circle Ramp gradient and Rectangle nodes AE and Nuke Tutorials In this chapter s tutorials you ll create new projects and scripts In After Effects you ll work with interlaced
16. menus to the bottom of the properties panel For example TIFF adds a Data Type bit depth and a Compression menu Once you ve set the quality menus click the Render button In the Frames To Render dialog box enter the desired frame range For instance if you want to render frame 10 enter 10 If you want to render frames 5 to 20 enter 5 20 Writel Write Node channels rgb gt B red B amp B geen amp blue file C Program Files Nuke5 1 1 test t t_tga proxy colorspace default v premultiplied raw data views main file type targa compression RLE v render_order 1 Render Figure 1 30 Write node properties panel 30 CHAPTER 1 m Setting Up a Composite Interlacing and 3 2 Pulldown in Nuke Nuke 5 1 carries a hidden DelInterlace node To access the node press the X key to bring up the Command Line window With the Script radio buttons set to TCL enter DeInterlace in the cell and click OK note the capitalization A DeInterlace node is added to the Node Graph Connect the DeInterlace node to the output of a Read node that carries interlaced footage The interlacing is removed However since the DeInterlace node carries no adjustable parameters the output may be scaled verti cally To correct this connect Transform and Reformat nodes to scale and fit the output back to the project reso Read lution For example in Figure 1 31 interlaced HDTV interlaced 16 tga footage is imported The DeInterlace node removes the
17. of 23 976 fps style where W indicates a whole frame and S indicates a split frame Split frames are composed of two neighboring whole frames Tips amp Tricks 24Pa Pulldown After Effects includes a Guess 24Pa Pulldown button in the Interpret Footage dialog box This is designed to remove the pulldown created by 24p Advanced video systems which record 24 pro gressive fps within a 30 fps interlaced video format Nuke Scripts Nuke composites are called scripts To create a new script choose File gt New from the main menu bar For a review of Nuke panes and menus see the introduction To edit the script s global properties choose Edit gt Project Settings In the properties panel the Frame Range parameter determines the duration the Fps parameter sets the frame rate and the Full Size Format parameter establishes the composite resolution A Nuke parameter is any property with a slider numeric cell or check box Importing Files To import footage into a Nuke script create a Read node To do so RMB click in the Node Graph and choose Image Read from the menu Throughout this book the RMB click technique is used almost exclusively when creating new nodes You can also LMB click the Image button at the top of the left toolbar and choose Read from the menu Once the Read1 node exists its properties panel opens in the Properties pane If the properties panel is not visible double click the Read1 node in the Node Graph You
18. repeating frames of the 24 fps footage To remove the resulting hesitation in the movement you can apply time warping and frame blending which is detailed in Chapter 12 If you drop 30 fps footage into a 24 fps composi tion frames are removed from the 30 fps footage To remove resulting skipping within the movement you can apply time warping and frame blending In addition After Effects provides a means to remove a 3 2 pulldown that was previ ously applied to footage For example if motion picture footage was transferred to video m Setting Up a Composite 23 and that interlaced video is imported into After Effects you can remove the 3 2 pulldown and thus return the motion picture footage to 23 976 fps which is close to its original 24 fps This process is commonly referred to as inverse telecine To apply inverse telecine open the Interpret Footage dialog box set the Separate Fields menu to the appropriate field domi nance and click the Guess 3 2 Pulldown button see Figure 1 21 The program identifies the style of pulldown and removes the duplicated frames Different pulldown styles repeat the original film frames in different patterns Fields and Pulldown Separate Fields Upper Field First W Preserve Edges Best Quality Only Figure 1 21 The Fields And Pulldown section of the Interpret Footage dialog Remove Pulldown box The WSSWW listed by the Remove Pulldown menu is the identified pulldown Effective framerate
19. select the first image of the sequence By default the program imports consecutively numbered frames 14 CHAPTER 1 m Setting Up a Composite as a single unit This assumes that the files follow the following naming convention name extension Extension is the three letter file format code such as tga The program also requires a consistent number of numeric placeholders within the sequence For example if a sequence has 200 frames there must be three placeholders as with name ext When footage is imported it s placed in the Project panel By default an imported image sequence or movie is assumed to be a particular frame rate such as 30 fps To change the frame rate interpretation select the footage name in the Project panel RMB click and choose Interpret gt Main from the menu In the Interpret Footage dialog box change the Assume This Frame Rate value to a number of your choice and click OK Tips amp Tricks Missing Files and Assumed Frames Rates If you open a project file and find that the footage is missing due to an incorrect file path you can retrieve it by selecting the footage name in the Project panel RMB clicking and choosing Replace Footage gt File You can change the default frame rate interpretation for all imported footage by choosing Edit gt Preferences gt Import and changing the Frames Per Second cell Using the Layer Outline To add imported footage to a composition as a layer LMB drag
20. set of transformations and special effect filters The layers are stacked and processed in order from bottom to top see Figure 1 5 If there are three layers the bottom layer and middle layer are blended and then the result is blended with the top layer and utilized digital still or image sequence as a node The output of a node is connected to the inputs of other nodes which may be special effect filters 2 fj engine_spec tga 3 fj engine_fan_rim tga 4 fj engine_rim tga 5 fj engine_ref_holdout tga 6 fj engine_reflect tga 7 fj engine_ao tga 8 fj engine_self_shadow tga 9 Wj engine_diffuse tga Node based programs on the other hand represent each imported input output controls and viewers see Figure 1 6 Any given node accepts 10 yj engine_shadow tga a limited number of inputs However the output of a node may be con 11 Vj engine_background tga nected to an almost unlimited number of nodes through their inputs Node as a term refers to a discrete unit used to build linked data structures The data structure in Nuke and similar node based programs is referred to as a Figure 1 5 The layer outline in the Timeline panel of After Effects The 11 layers are processed in order from tree graph node tree or node network More specifically the structure is a bottom to top Directed Acyclic Graph DAG wherein data flows in one direction along the node connections The direction is usually indicated
21. the Composition Mini Flowchart button When clicked the button displays the names of composi tions immediately upstream and downstream of the active composition Upstream nodes pro vide information while downstream nodes accept information Previewing a Composition To play back the timeline use the playback controls in the Time Controls panel As the timeline is played each frame is composited and stored in a cache Once all the frames have been composited the timeline is able to achieve real time playback speeds The playback speed is indicated by an Fps readout in the Info panel The target frame rate is determined by the Frame Rate parameter of the Project Settings dialog box However you can change the rate through the Frame Rate menu of the Time Controls panel to achieve a different playback rate temporarily Rendering a Composition To render out a composition select the composition name in the Project panel and choose Composition gt Add To Render Queue A Render Queue tab is added to the Timeline panel see Figure 1 16 Each queued item in the Render Queue is divided into four sections Render Settings Output Modules Log and Output To Render Settings controls the quality of the render To adjust the quality click the words Best Settings In the Render Settings dialog box you can adjust the Quality prop erty Best Draft or Wireframe choose a custom frame range and toggle on or off render features such as Motion Blur
22. the camera zoom appears smooth In reality After Effects has incorrectly interpreted the field dominance as upper This is not vis ible in the viewer of the Composition panel This is due to the program displaying only one field per frame when playing back the timeline for the composition To see all the fields double click the footage name This opens the footage in the Footage panel To step through the fields one at a time press the Page Down and Page Up buttons Page Down moves forward starting with the dominant field for each frame Page Up moves backward Note that the fields appear out of order Play back the footage using the Footage panel s time controls The motion appears erratic To solve the field problem select the interlaced mov footage in the Project panel RMBe click and choose Interpret Footage gt Main In the Interpret Footage dialog box change Separate Fields to Lower Frame First and click OK Play the footage using the Footage panel s time controls The motion is now smooth that is the fields are no longer out of order To convert the field separated footage into progressive frame footage you can ren der out an image sequence To do so select Comp 1 in the Project panel and choose Composition gt Add To Render Queue A Render Queue tab is added to the Timeline panel with Comp 1 listed as the first queue Click the word Lossless In the Output Module Settings dialog box change the Format menu to Targa Sequence
23. the expense and difficult maintenance of the Flame and Inferno systems artists have traditionally learned them by apprenticing under an experienced compositor on site Between the two programs Inferno is considered the more advanced due to resolution independence and advances in hardware design After Effects is distributed by Adobe and is now bundled with its production set of software It was developed in the early 1990s and was purchased by Adobe in 1994 Since that time the After Effects interface has stayed fairly consistent with minor adjustments accompanying every release Because of its low price and ease of use it is employed widely in various graphics related fields by professionals students and hobbyists That said professional compositors at larger studios tend to employ it as a secondary compositing program Of all the programs discussed in this section After Effects is the only one that is layer based Shake was developed by a team of compositors at Sony Pictures Imageworks in the mid 1990s In 2002 Apple purchased the software Shake has been a preferred compositor in the visual effects industry due to its long time support of high resolutions such as 2K 4K and IMAX Shake sup ports 8 16 and 32 bit workflows Nuke was developed by Digital Domain in 1993 as an in house compositor It was released to the public in 2002 In 2007 The Foundry a London based software distributor took over the development of the program Nu
24. to achieve real time playback speeds The playback speed is indicated by the Desired Playback Rate cell which is to the immediate right of the playback controls The target frame rate is determined by the Fps parameter of the Project Settings properties panel However you can change the value in the Desired Playback Rate cell to temporarily achieve a different playback rate To create a Flipbook select the node whose output you wish to see and choose Render gt Flipbook Selected from the menu bar In the Frames To Flipbook dialog box enter a frame range Each frame of the composite is written to a disk cache as an RGB file with an rgb extension Once the render is complete the IRIDAS FrameCycler window opens FrameCycler is an external program and thus has its own unique interface see Figure 1 29 Figure 1 29 FrameCycler window m Setting Up a Composite 29 To center the rendered movie in the FrameCycler viewer press Ctrl Home To scroll within the viewer Ctrl MMB drag To zoom in or out set the Zoom menu directly above the time controls To see the render at full size set the Zoom menu to Resample Off You can interactively scrub the timeline by RMB dragging left or right in the viewer or LMB dragging the playhead bar on the timeline The time controls function as they do in any standard player The first time you play the timeline the rendered frames are reloaded into memory You can save a flipbook movie as an image sequence
25. Footage panel is displayed Center Lower field of same frame Note the significantly higher position of the bottle and index finger Right Upper field of the same frame as seen in the viewer of the Composition panel If you are working with D1 or DV footage it s generally best to leave the field domi nance interpretation to the program However you can choose a different field dominance or select a field dominance for a different video format through the Interpret Footage dialog box To access this select the footage name in the Project panel RMB click and choose Interpret gt Main from the menu You can set the Separate Fields menu to Off Upper Field First or Lower Field First If field dominance is chosen incorrectly for a piece of footage objects will appear to move erratically in the viewer of the Footage panel If the footage pos sesses a field dominance but the Field Separation is set to Off the fields are combined with out averaging and heavy artifacts appear around objects in motion Various interlacing de interlacing plug ins such as RE Vision Effects Twixtor are available for After Effects and are generally superior to the program s native tools when handling interlacing tasks 3 2 Pulldown in AE As mentioned earlier in this chapter a 3 2 pulldown is required when converting between 24 fps and 29 97 or 30 fps If you drop 24 fps footage into a 29 97 fps composition After Effects automatically applies the pulldown by
26. Time F Take Snapshot G Show Last Snapshot H Show Channel I Resolution Down Sample Factor Popup J Region Of Interest K Toggle Transparency Grid L 3D View Popup M Select View Layout N Toggle Pixel Aspect Ratio Correction O Fast Previews P Timeline O Comp Flowchart View R Reset Exposure S Adjust Exposure 18 CHAPTER 1 m Setting Up a Composite While the switches and menus will be described throughout the remaining chapters a few are worth noting here Magnification Ratio Popup menu zooms in or out of the view To scroll left right or up down in a viewer LMB drag with the Hand tool to the right of the Selection tool Choose Grid And Guide Options menu allows you to apply Title Action Safe Grid and Ruler overlays to the view Tips amp Tricks Title Action Safe and Overscan The Title Action Safe overlay is designed for SDTV It offers a quick way to make sure critical text and action doesn t get too close to the edge of frame Due to the design limitations of CRT based televisions the frame edge is lost and is not seen by the viewer This lost region is known as over scan Although digital televisions offer greater control of the broadcast image display overscan remains a feature For example HD televisions generally show the viewer the central 1776x1000 set of pixels out of a possible 1920X1080 pixels Ifa project is intended for motion picture film the Title Action Safe overlay doesn t app
27. amma pick a particular dis play LUT and switch between 2D and 3D camera views A E Viewerl B C E F G H tgba tgba alphe RGB A Merge v Er ad 2D CETS 4 84 yi Bi f OH e PZ K M N OPQ R Saal Figure 1 27 Top of the Viewer pane A Channels B Channel In Alpha C Display Style D Wipe controls E Zoom F View Selection G 3D View Lock H Default Camera Light I Gain via stops J Gain via slider K Gamma Toggle L Gamma via slider M Toggle Proxy Mode N Downrez O Region Of Interest P Update O Pause R Display_LUT S Input_process T Cliptest While most of the Viewer pane menus and controls will be described throughout the remaining chapters a few are worth noting here Channels determines which channels are available for view in the viewer To cycle through the chosen channels press the R G and B keys while the mouse hovers over the Viewer pane You can also step through the channels by changing the Display Style menu Channel In Alpha allows you to select a different channel to display where the alpha channel would be normally For example you can change the menu to Rgb red and press the A key while the mouse hovers over the Viewer pane to view the red channel If the menu is set to None pressing A will display the alpha channel Zoom controls its namesake You can interactively zoom in the Viewer pane by Alt MMB dragging You can scroll in the Viewer pane by Alt LMB draggin
28. d color space which are discussed in Chapter 2 Choosing a Color Space To create a new composition choose Composition gt New Composition The Compo sition Settings dialog box opens allowing you to set the composition s critical properties The Preset menu sets common formats and their appropriate resolution frame rate and PAR see Figure 1 9 You can also manually set the resolution Width and Height cells plus enter a custom value into the Frame Rate cell You can manually choose different PARs through the Pixel Aspect Ratio menu The composition length is set by the Duration cell When a new composition is created it s placed in the Project panel and named Comp n see Figure 1 10 To see the composition as a tab in the Timeline panel double click the composition name If you create more than one composition each composition receives a separate tab in the Timeline panel Initially a composition is empty However you can cre ate layers for the composition by importing and adding footage see the next two sections Start numbering frames at lo Setting Up a Composite 13 Composition Settings Figure 1 9 The Composi tion Settings dialog box Figure 1 10 The expanded Project panel with 3 compositions and 12 pieces of footage Importing Footage To import an image image sequence QuickTime movie or AVI movie into After Effects choose File gt Import gt File If you are importing an image sequence
29. ead In the Read2 node s properties panel browse for square tif in the Footage folder on the DVD Connect the viewer to Read2 A city square is displayed However the view adapts to the new larger resolution of the square tif image This is indicated by the 2048 1556 notation at the top right of the view frame see Figure 1 32 With no nodes selected RMB click and choose Merge gt Merge Connect the viewer to the Mergel node Connect input B of the Mergel node to the output of the Read2 node Connect input A of Mergel to the output of Read1 The Mergel node applies a blending operation to combine the two images Because symbols tga carries an alpha channel it appears on top of the city square However since square tif is larger than symbols tga and the project resolution the view frame remains fixed at 2048x1556 In addition the symbols graphic is forced to the bottom left of the frame see Figure 1 33 If you were to render the Mergel node s output the resolution would remain 2048x1556 To force the Mergel node to create a project sized resolution feed the Read2 node through a Reformat node To do so select the Read2 node RMB click and choose Transform gt Reformat A Reformat node is inserted after Read2 The composition instantly returns to the proper size of 1024x778 and the symbols take up the entire m Setting Up a Composite 33 frame The Reformat node forces the Read2 output to conform to the output forma
30. erties panel and enter a new name into the top cell m Setting Up a Composite e To duplicate a node with its current setting select the node and choose Edit gt Duplicate from the menu bar e You can clone a node by selecting the node and choosing Edit gt Clone from the menu bar Cloning differs from duplication in that the cloned node maintains an active link to the original node see Figure 1 24 Thus if the properties of the original node are updated the updated information is passed to the cloned node You can sever the link between the clone and the original by choosing the cloned node and selecting Edit gt Declone Figure 1 24 A cloned node left is automatically connected to the source node right as indicated by the orange pipe and the orange C symbol at the top left corner of each node icon e To help organize the node network you can force bends into pipes To do so choose the node that is upstream that is provides the output RMB click and choose Other gt Dot A dot icon is inserted into the pipe see Figure 1 25 You can LMB drag the dot and thus force a right angle into the connection The dot carries no parameters You can also insert a dot by pressing the Ctrl key while the mouse is in the Node Graph A diamond appears at the midpoint of every pipe Continue to hold the Ctrl key while LMB dragging a diamond The diamond is instantly converted to a dot e To zoom in or out of the Node Graph Alt MMB dra
31. es logical for specific media m Resolutions and Frame Rates 9 Common Resolutions and Aspect Ratios You can break image resolutions into three categories SDTV HDTV and motion pic ture film SDTV Standard Definition Television includes broadcast television and video that possesses fewer than 720 lines of vertical resolution SDTV may be analog or digital HDTV High Definition Television includes broadcast television and video that possesses 720 or more lines of vertical resolution HDTV as a newer format is digital Motion pic ture resolutions on the other hand are dependent on film scanner and film recorder tech nologies Nevertheless resolutions common to film scans are similar to resolutions captured by the latest generation of HD digital video cameras Video and broadcast television resolutions are determined by a number of international standards including NTSC PAL SECAM ATSC and DVB NTSC National Television System Committee is the standard for North America Japan South Korea Taiwan and parts of South America PAL Phase Alternating Line is the standard for Europe South America Africa India Australia and parts of the Pacific Rim SECAM SEquentiel Couleur Avec M moire is the standard for France Russia and parts of Africa PAL and SECAM use the same SDTV resolution and frame rate ATSC Advanced Television Systems Committee is the digital broadcast successor for NTSC in North America DVB Digital Video Br
32. existed in the same location or scene Digital compositing is closely related to photomontage and compositing without the word digital Photomontage is the process of cutting apart reassembling and rephotographing photographic prints Compositing as it s used for professional pho tography is the digital assembly of still images compositing when used this way is often referred to as Photoshopping The compositing and composites mentioned in this book refer to digital compositing Professional digital compositors are simply known as compositors While this book focuses on the theoretical and technical aspects of digital composit ing it dedicates a limited amount of space to the aesthetic component Ultimately the suc cess of a composite does not rely solely on specific effects or nodes Instead a successful composite makes a particular shot look real or appear attractive If the composite is a visual effect then the goal is to make all the elements background plate computer graphics CG renders matte paintings and so on look like they exist in a real world location If the com posite is for feature animation and the sets and characters are fantastic the goal is to make the elements visually interesting yet at the same time plausible for the world fabricated by the story If the composite uses abstracted motion graphics and text for a commercial the goal is to make the elements fascinating exciting or just plain worth watching W
33. fashion in the Node Graph Here are a few approaches to keep in mind To connect two nodes LMB drag an unused pipe connecting line from one node and drop it on a second node Each pipe has a specific input or output function Input pipes are indicated by a line and arrowhead pointing toward the node see Figure 1 23 Input nodes are generally labeled The exception to this rule is a Mask input which takes the form of an inward pointing arrow stub at the right side of the Input A pipe Input B pipe node Output pipes are indicated by an outward pointing arrow stub at the bot i i tom edge of the node ad oaa Mask input If a node is selected and a new node is cre a ee eee arrow stub ated the new node is automatically con Output arrow stub nected to the selected node s output To disconnect a node LMB drag the pipe Figure 1 23 Pipes and arrow stubs of a node away from the connected node When you release the mouse button the pipe is bro ken You can also select the node that is downstream that is the one that receives the input and press Ctrl D To select a node LMB click the node icon To open a node s properties panel double click the node icon To select multiple nodes Shift click the node icons To disable a node so that it no longer influences the node network select the node and press D To enable the node press D again To delete a node select the node icon and press the Delete key To rename a node open its prop
34. fer a means to separate 3D objects In this case foreground mid ground and background objects are separated The final composite is color graded Depth of field is applied to the composite to soften the immediate foreground and background Artificial glare is also added to make the daylight lighting appear more intense 3 A CG render featuring a medical lab is imported into the composite Although con vincing it lacks people 4 Two actors are shot against greenscreen After greenscreen removal and additional rotoscoping they are imported into the composite To allow the central actor to appear as if he s walking across the floor the composite is converted to a 3D environ ment The footage of the central actor is converted into a 3D card and is animated moving across the z axis To help sell the effect reflections for each leg are applied to separate cards and are animated individually To create the reflections copies of the actor footage layer are vertically inverted and masked Figure 1 4 Before and after images of two shots composited by Tonya Smay for a medical center commercial Images courtesy of Tonya Smay m Layers vs Nodes 7 Layers vs Nodes After Effects and Nuke exemplify the two major approaches to composit 4 aT engine _fog tga ing layer based and node based Layer based programs represent each imported and utilized digital still or image sequence as a layer along a time line Each layer possesses its own
35. g Pressing the MMB will maximize the view frame automatically without cropping the edges Downrez displays a simplified version of the viewer output If Downrez is set to 1 the viewer displays the output at 100 quality If it s set to a value other than 1 pixels are m Setting Up a Composite 27 averaged to speed up the viewer update For example if the Downrez menu is set to 16 the project s horizontal and vertical resolution is reduced to 1 16th Toggle Proxy allows you to switch to a low resolution version of the composite For this to work the Proxy check box in the Project Settings properties panel must be selected The degree to which the image is reduced is based upon the Proxy Mode menu which can be set to Format or Scale If the menu is set to Scale the proxy works like the Downrez menu whereby pixels are averaged together If the Proxy Mode menu is set to Format the proxy resolution is based on the Proxy Format menu Tips amp Tricks Proxy Resolutions The Read node supports the importation of a full resolution and a proxy resolution version of the same piece of footage The full resolution version is loaded through the File parameter while the proxy resolution version is loaded through the Proxy parameter If the Toggle Proxy button is toggled on in the Viewer pane the proxy footage is used Wipe displays the output of two nodes simultaneously within the same viewer frame see Figure 1 28 To activate the wipe
36. g To pan Alt LMB drag To frame the node network automatically MMB click while the mouse pointer is over Figure 1 25 A dot creates a bend in the Node Graph a pipe Using the Viewer Pane and Viewers To view a composite you must connect a viewer to the node network By default a Viewer 1 node is provided To connect Viewer 1 LMB drag the 1 pipe and drop it on top of the node you wish to view Once a viewer is connected its output is displayed in the Viewer pane You can also connect a viewer by selecting the node you wish to view and pressing the 1 key You can connect more than one node to a viewer see Figure 1 26 To do so select the nodes one at a time and press the next available viewer number on the keyboard such as 2 3 or 4 To have each connection s output appear in the Viewer pane press the appropriate number key You can create additional viewers and connect each viewer to a different node To do so choose Viewer gt Create New Viewer from the menu bar If more than one viewer exists in a script each viewer receives a tab in the Viewer pane 25 26 CHAPTER 1 m Setting Up a Composite Premult 2 Viewer2 Figure 1 26 One viewer connected to three nodes Aside from displaying the outputs of various viewers the Viewer pane carries a num ber of menus and controls see Figure 1 27 These include the ability to control the timeline display different channels adjust the viewer f stop gain and g
37. hatever the destination of the composite it always pays to study related fields In particular photography cinematography stage and film lighting and classic painting will help you develop an eye for what works Composition color balance light quality and shadow quality are important aspects of these fields and are equally applicable to composit ing As you follow the step by step guides and tutorials in this book ask yourself how each composite can be improved Not only are there many different approaches to each compos iting task there also are numerous ways to fine tune any given shot Compositing Examples If you are fairly new to compositing it may be difficult to imagine what types of foot age rendered elements or layers are regularly combined As such several examples are included in this chapter All the listed techniques are demonstrated in the various chapters of this book Freestyle Collective for Cartoon Network Figure 1 1 shows eight steps of an After Effects composite created by Entae Kim at Freestyle Collective a collaborative design and production studio in New York City To read an interview with Entae Kim see Chapter 7 Masking Rotoscoping and Motion Tracking The composite is one shot of an extended network ID identification that features popular Cartoon Network characters battling each other The breakdown is as follows 1 A gradient is used to create a sky Stock images of clouds are added with
38. he term digital compositing was used Can you describe the route you took to ILM DH While at school at Cal Arts I was doing graphics for commercials and titles with visual effects I didn t run an optical printer I was prepping work for optical printers and art directing work with optical printers So that was my focus in the early 1980s art direction and design along with animation and film graphics really Initially I was just freelancing for small companies in L A T he first big studio I worked for was Dream Quest Images in the late 1980s My first feature film was Superman IV I also worked at a place called Chandler Group on Pee Wee s Playhouse I worked for Universal Studios on feature film trailer titles which was kind of a niche at that point In the early 1990s I joined Buena Vista Visual Effects the early digital effects division of Walt Disney Studios that was the real transition into digital compositing And I worked there until I came to ILM 11 years ago LL Approximately how many compositors are at ILM at any given time DH It fluctuates based on the number of shows that we re working on at once We might have three to five big shows at once going through here at any time The size of the crew will expand and contract based on that W hen I got here in 1998 there were around 20 staff compositors At present I m guessing that there are around 60 to 70 including freelancers LL Since you
39. ich records progressive frames at 24 fps Other cameras offer 24p Advanced which records 24 fps by repeating frames with a 30 fps format The frame rate of PAL SECAM and DVB video and broadcast television is 25 The ATSC HDTV formats 1080p 1080i and 720p as well as 480p EDTV support a frame rate of 30 If the video is interlaced 30 fps is sometimes expressed as 60 or 60 fields per second Tips amp Tricks NTSC and ATSC Frame Rates When a frame rate Is listed for an NTSC or ATSC SDTV EDTV or HDTV format it is usually rounded off Thus 30 fps is actually 29 97 fps and 24 fps Is actually 23 98 fps When whole value frame rates are listed for PAL or DVB formats the frame rate is accurate Note that 29 97 isa simplification of the more accurate 30 1 001 and 23 98 is a simplification of 24 1 001 Tips amp Tricks Frame Rate Conversions Converting between frame rates has been a problem since the advent of television Converting from 24 fps to 30 fps requires a 3 2 pulldown whereby frames must be duplicated This leads to hesitation in the motion known as judder Converting from 30 fps to 24 fps requires the removal or averaging of 6 frames per second Converting between different international video and broad cast standards is equally difficult and often leads to some type of motion artifact Thankfully recent improvements in time warping and optical flow techniques allow compositors to change frame rates without unduly affecting the f
40. io in New York City To read an interview with Aaron Vasquez see Chapter 11 Working with 2 5D and 3D The composite is one shot of a commercial for Sharp featuring the Aquos television The breakdown is as follows 1 A peacock is filmed against greenscreen The bird slowly rotates on a turntable 2 The peacock footage is motion tracked The tracking information is brought into Flame and applied to a 3D camera Simple geometry is added to the background in the composite Flame provides geometry primitives and is able to import geometry files After greenscreen removal the peacock footage is placed over the background Since the 3D camera uses tracking information from the footage it dollies at an appro priate speed and perspective to fit the background to the peacock Hence the 3D background doesn t slide under the peacock s feet A shadow is created by offsetting transforming and darkening the peacock footage The body of the bird is removed and replaced by a CG body thus creating different color feathers The motion tracking data ensures that the CG fits tightly to the bird 3 A prop tail shot against greenscreen is brought into the composite and layered to cre ate new tail feathers for the peacock 4 The layered feathers are fit to the body through spline warp tools and motion tracking The defor mation of the feathers is animated over time to create the illusion of rustling A separate iteration of the feathers is used
41. ions But overall it s pretty seamless At the beginning of a show you think Oh my God it s HD It s all going to be different And then once you re working you realize that it s the same as working in film It s pretty much invisible Additional Resources The Full Interview To read the full interview with Dorne Huebler see the Interviews folder on the DVD 36 Michael Coleman CHAPTER 1 m Setting Up a Composite Interview Michael Coleman Adobe Seattle Washington Michael Coleman graduated with a degree in business economics from Seattle University He went on to work as a graphic designer visual effects artist and compositor for such companies as Aldus and Will Vinton Studios In 1999 he joined Adobe and helped redesign the Adobe Creative Suite In 2007 he became the product manager of After Effects Adobe Systems Incorporated was founded in 1982 by John Warnock and Charles Geschke Although its initial products were PostScript tools and digital fonts the company has gone on to develop a wide array of desktop publishing digital imaging digital editing and compositing software As of 2009 Adobe had grown to over 7 000 employees with offices in San Jose Seattle Orlando and San Francisco as well other cities in the United States and abroad LL What are your duties as product manager MC The product manager position has many facets but my main responsibility is to define the product s
42. joined ILM you ve served as a compositing supervisor How many composi tors would you work with on one project DH I was compositing supervisor for Star Wars Episode II At one point we had close to 35 compositors in my group A smaller show may only need 6 to 10 people A lot of the times there are technical directors who will do their own compositing so you ll work with them as well LL Do you prefer working with the proprietary compositing software or off the shelf com positing software DH What I ve found is with every package I use I always find things that I just love E very package also has idiosyncrasies like this is the one thing that bugs me about it So I think that it s really about the type of work you re doing and whether one program might be more efficient than another It really depends on what you re up to LL ILM helped popularize the use of HD digital video for feature film work What has been your own experience with HD in comparison to film DH I m actually trying to think about the last time I worked on an HD show I mean we ll have elements that are shot in HD and it can be really convenient because you don t have to get a film scan I think it s been three or four years since I ve worked on an all HD show When you re working with HD you re going to deal with different green channel struc ture for instance It can present challenges for greenscreen extract
43. ke has always enjoyed 32 bit floating point architecture and has been ported to every major operating system Although Nuke continues to be used by Digital Domain it tends to be a secondary program at other animation studios However many com positors have found it to be a worthy replacement for Shake which has suffered from lack of development in the last several years At the time of this writing several major studios including Industrial Light amp Magic and Weta Digital have purchased site licenses for Nuke Fusion previously known as Digital Fusion is distributed by Eyeon Software Inc and has found its niche in episodic television feature visual effects and the video game industry Toxik is a relative newcomer to the Autodesk suite of programs and is aimed at high resolution film and video work In August 2009 Autodesk announced the integration of Toxik with Maya 2010 as such the use of Toxik which has been renamed Maya Composite will likely become more wide spread Combustion also distributed by Autodesk has long been an inexpensive desktop rival to After Effects Combustion is unique in that it is node based but offers a layer outline similar to After Effects Combustion due its architecture is best suited for low resolution projects Resolutions and Frame Rates Compositors are faced with a wide array of image resolutions and frame rates However international broadcast standards and motion picture precedents make the choic
44. le to render with an m Setting Up a Composite 21 alpha channel change the menu to RGB Alpha You can also choose to render straight or premultiplied alpha through the Color menu For information on alpha and premultiplica tion see Chapter 3 Finally the Output Module Settings dialog box offers a means to res cale or crop an output through the Stretch and Crop check boxes Note that the dialog box carries a Color Management tab which allows you to render a composite to a specific color space This process is discussed in Chapter 2 The Log section sets the style of an error log text file that s written to disk Output To sets the name and location of file s to be written To select a name and location click the current filename for example Comp1 avi The Output Movie To dialog box opens Enter the name into the file name cell using the format name extension for an image sequence and name extension for QuickTime or AVI movies For example test tga is suitable for a Targa image sequence with 10 to 99 frames because it includes two numeric placeholders Once the various render settings are selected you can launch the render by clicking the Render button at the top right of the Render Queue tab When the render finishes the queued item remains listed If you queue an additional composition it s added to the queue list You can delete an old queue by selecting the item name in the list and pressing the Delete key
45. ly Nevertheless due to projector apertures and masks a portion of the film frame is lost when shown in theaters To compensate for this some com positors import a custom field chart into the compositing program a field chart indicates the area of exposure and projection for a particular camera setup Toggle Mask And Shape Path Visibility if toggled off hides mask and shape paths Masks are discussed in Chapter 7 Masking Rotoscoping and Motion Tracking Take Snapshot when clicked captures the current view and stores it in a cache You can examine snapshots by clicking the Show Last Snapshot button Snapshots are use ful when comparing different frames or the results of different effect settings Resolution Down Sample Factor Popup menu reduces the resolution of the composi tion to speed up the viewer update If this is set to Full the composite is set to 100 quality If it s set to Half half the pixels are discarded and a pixilated view is thus created Region Of Interest if toggled on allows you to LMB drag interactively in the viewer to isolate a small area This improves the update speed of the viewer Toggle Transparency Grid if toggled on changes the empty black background of the viewer to a white and gray checkerboard This is useful for identifying subtle holes in a layer Toggle Pixel Aspect Ratio Correction if toggled on stretches non square pixels into square pixels For example if a composition is set t
46. o DV resolution with a 0 9 PAR Toggle Pixel Aspect Ratio Correction stretches the view horizontally to create a 1 0 PAR Note that the new PAR only exists in the viewer and does not affect the compos ite when it s rendered through the Render Queue Fast Previews if clicked reveals a menu with the different display and graphics card options available on your machine m Setting Up a Composite 19 The AE Flowchart After Effects can display compositions and their relationships as a flowchart node network To display the flowchart toggle on the Comp Flowchart View switch in the Composition panel or choose Composi tion gt Comp Flowchart View The flow chart is opened in a new Flowchart panel Mise Footage node You can display footage solids layers and effects nodes by toggling on the display Faste Layer node with effects list buttons at the bottom left of the Flowchart panel Connection lines show the flow of information see Figure 1 15 You can col lapse a composition node and thus hide its inputs by clicking the sign at the top of the node icon Note that the flowchart is intended as reference Connections cannot be changed within the flowchart view Figure 1 15 Flowchart view in the Viewer panel Tips amp Tricks Composition Navigator After Effects CS4 adds the Composition Navigator bar to the top of the Composition panel The bar displays node network information for nested compositions The bar includes
47. oad casting is the digital broadcast successor for PAL and SECAM in Europe Australia and parts of Africa Image aspect ratios are intrinsically linked to resolutions An aspect ratio is repre sented as x y or x where x is the width and y is the height For example the SDTV aspect ratio can be written as 1 33 1 or 1 33 That is SDTV has a width that s 1 33 times greater than its height HDTV has an aspect ratio of 16 9 or 1 78 Mixing different aspect ratios leads to compositional problems For example broadcasting SDTV on a high definition TV requires the footage to be stretched horizontally or letterboxed with two side bars Broadcasting HDTV on an SDTV set requires the footage to be cropped at the sides or let terboxed with top and bottom bars In terms of compositing mixing footage with different aspect ratios necessitates additional transformations to fit the components together See the tutorials at the end of the chapter for more information In addition each resolution carries a specific Pixel Aspect Ratio PAR A PAR is the mathematical ratio between the pixel width and height A square PAR has an equal width and height and is expressed as 1 1 or 1 0 A non square PAR has an unequal width and height Non square PARs are feasible because television hardware is able to stretch non square pixels into square pixels at the point of display For example NTSC SDTV has a PAR of 10 11 which is rounded off as 0 9 Thus NTSC SDTV pixels a
48. olutions remain the same but the NTSC PAR becomes 1 21 and the PAL PAR becomes 1 42 HDTV 1080 and HDTV 720 There are two HDTV resolutions 1080 and 720 The 1080 format runs 1920x1080 while the 720 format runs 1280x720 The 720 format utilizes progressive frames as is indicated by the p in 720p The 1080 format supports interlaced and progressive variations as is indicated by the names 1080i and 1080p Although the resolutions for ATSC HDTV and DVB HDTV are identical the frame rates remain different See the next two sections for information on frame rates and interlacing HDTV formats are often written as height fields frame rate For example 720p24 is 1280x720 with 24 progressive frames per second 1K 2K 3K and 4K Ifa resolution ends with K it refers to the number of pixels available horizontally You can multiply the number by 1024 to get the result For example 2K is 2048 while 4K is 4096 These resolutions are often employed by motion picture film scanners and recorders As such the number of vertical lines of resolution is dependent on the aperture used An aperture is an opening in a plate that allows light to strike the film or the digital sensor In order for a film scanner to capture the full motion picture frame it must match its aperture to the one used by the film cam era Two common film formats Academy and Full Aperture also known as Super 35 or full ap use two different apertures which leads to two different resoluti
49. ons Full Aperture uses the full width of the film to expose the frame no room is left for the optical soundtrack Full Aperture scans create a 2048x1556 2K image Academy shrinks the exposure to make room for the optical soundtrack Thus the 2K Academy resolution is reduced to 1828x1332 Note that projectors employ apertures that have a slightly smaller opening than camera scanner and recorder apertures thus the edges of the image are cropped Also note that HD digital video cameras operate at common K resolutions For example a 4096x2048 resolution is referred to as 4K 2 1 Cinemascope and VistaVision Cinemascope is an anamorphic system that uses a special lens to squeeze an image horizontally so that it fits either the Academy or Full Aperture format The projector uses a matching lens to restretch the image into its correct shape A common Cinemascope scan size is 1828x1556 In this case the compositing program must set the PAR to 2 0 to view the image in a nonstretched fashion VistaVision also known as 8 perf rotates the film frame by 90 so that the frame has twice the film stock with which to work A common VistaVision scan size is 3096x2048 Common Frame Rates There are three common frame rates 24 25 and 30 The frame rate of motion picture film is 24 The 1080p and 720p ATSC HDTV for mats in addition to 480p EDTV support 24 fps variations Some digital video cameras m Resolutions and Frame Rates 11 support 24p wh
50. ootage For more information on time warping and optical flow see Chapter 12 Advanced Techniques Interlaced vs Progressive The process of interlacing breaks each frame of video into two fields One field carries the even line numbers and a sec ond field carries the odd lines numbers see Figure 1 7 When interlaced footage is broadcast or played as video the fields are displayed one at a time Hence NTSC SDTV displays 60 1 001 fields per second often rounded to 59 94 and PAL SDTV displays 50 fields per second Interlacing provides improved picture quality without requiring additional bandwidth In con trast progressive frames are not split apart but are displayed intact CG renders for example are generally delivered to a com positor as progressive frames Figure 1 7 Close up of interlaced frame The footage features a rapid camera zoom in If the camera movement was slower the interlacing would be less perceptible 12 CHAPTER 1 m Setting Up a Composite Tips amp Tricks Progressive Frame Tutorials 21 out of 22 tutorials included in this book use progressive frame footage Any footage that was shot interlaced has been converted to progressive frames This was done to keep the tutorials relatively compact and to place the emphasis on various techniques tools effects and nodes In addition this allows footage to be shared between After Effects and Nuke At present Nuke possesses a limited toolset for
51. or Frame Blending see Figure 1 17 By default Quality is set to Best and the full frame range of the timeline is used However the Field Render and 3 2 Pulldown options are off by default see the next section 20 CHAPTER 1 m Setting Up a Composite All Renders Current Render gt Current Render Details gt Render Settings ess Settings Lal Trapanin Haki Proxy Use En x Effects Current Settings Solo Switches Current Settings Color Depth Current Settings 5 Frame Blending A On For Checked Layers Frame Rate Field Render Off Use comp s frame rate 29 97 3 2 Pulkdown ot Use this frame rate Bo Skip existing files allows multi machine rendering Figure 1 17 The Render Settings dialog box The Output Module section sets the render format To choose a different format click the word Lossless In the Output Module Settings dialog box the Format menu lists all the formats supported by After Effects that are detected on the local machine see Figure 1 18 QuickTime AVI Video For Windows and Windows Media formats are suitable for tests while image formats such as Targa and TIFF are superior for final renders For more infor mation on image formats see Chapter 2 Once a specific format is selected you can adjust the format compression and quality settings by clicking the Format Options button The Channels menu determines which channels are rendered For examp
52. osite Generally node based systems do not require precomposites or precomps Precomps are necessary with layer based systems because it is difficult to send outputs of par ticular layers or filters to the inputs of other layers High end feature animation and visual effects work is generally created on node based systems Flame Inferno Shake Fusion Toxik and Combustion are node based 8 CHAPTER 1 m Setting Up a Composite Industry Perspective Compositing Software Overview In preparation for this book 19 expert compositors from feature animation studios visual effects houses and commercial production facilities in Los Angeles New York and San Fran cisco as well as New Zealand and the United Kingdom were interviewed As such a survey of popular compositing software was taken The two most consistently named programs were Flame or its sister Inferno and After Effects These were followed by Shake and Nuke Fusion Toxik and Combustion were used more sporadically A few studios including Sony Pictures Imageworks and DreamWorks Animation continue to use proprietary compositing software Flame and Inferno are distributed by Autodesk and are prized for their real time high resolution workflow They are strongly favored in commercial production where clients prefer to sit in on color grading and other final adjustments Seats of Flame and Inferno are extremely expensive and can run several hundred thousand dollars Because of
53. ove All Attributes Into The New Composition If more than one layer is selected only the Move All Attributes Into The New Composition radio button is available Click the OK button m Setting Up a Composite 17 Sk New composition name Pre comp 1 Leave all attributes in Comp 1 Use this option to create a new intermediate composition with only greenfish 00 29 tga in it The new composition will become the source to the current layer This option is not available because more than one layer is selected f Move all attributes into the new composition Use this option to place the currently selected layers together into a new intermediate composition I Open New Composition Cancel Figure 1 13 The Pre compose dialog box 2 If a single layer is selected and Leave All Attributes In Comp is chosen the selected layer is left at its original location However a duplicate of the layer is placed in a new composition with a name determined by the New Composition Name cell If Move All Attributes Into The New Composition is selected the selected layer or layers are moved to the new composition The new composition is placed at the layers original location 3 You can nest transform or apply effects to the newly created layers within the new composition as you would any other composition You can manually create a precomp by rendering a composite through the Render Queue and importing the resulting footage
54. rack Matte menu buttons which convert the layer to a matte The Track Matte func tionality is discussed in Chapter 3 Interpreting Alpha and Creating Mattes Nesting Parenting and Precomping Compositions You can place one composition inside a second composition This is called nesting To do so LMB drag a composition from the Project panel and drop it on top of the layer outline of a different composition tab in the Timeline panel When a composition is nested the entire contents of the composition are represented by a single layer You can parent one layer to another by changing a layer s Parent menu to the right of the layer switches For example you can parent an upper layer to a lower layer When the lower layer is transformed the upper layer inherits the same transformation Transformations are discussed at length in Chapter 5 As discussed earlier in this chapter one disadvantage of the layer based system is the difficulty with which the output of an adjusted layer or layers is sent to another composi tion One workaround is to create a precomposite also known as a precomp through pre composing To precompose one or more layers follow these steps 1 Select a layer or layers in a layer outline Choose Layer gt Pre compose In the Pre compose dialog box enter a name into the New Composition Name cell see Figure 1 13 If a single layer is selected you can select a radio button for Leave All Attributes In Comp or M
55. re slightly taller than they are wide As such NTSC SDTV composites appear slightly squished on a computer monitor which uses square pixels However once the NTSC SDTV composite is trans ferred to video and broadcast the image appears normal A list of common resolutions follows If the PAR is not listed it s assumed to be 1 0 640x480 The visible broadcast size of NTSC SDTV as well as a variation of ATSC EDTV Enhanced Digital Television is 640x480 In addition 640x480 is a common size for web based videos in fact it s sometimes called PC Video A half size version 320x240 is often used for web based video that is severely restricted by bandwidth NSTC and PAL D1 D1 or D 1 was the first widely used digital video format Although D1 is no longer common its size is conducive to any compositing project destined for SDTV The NTSC square pixel version is 720x540 The NTSC non square version is 720X486 with a PAR of 0 9 The non square PAL version is 720X576 with a PAR 10 CHAPTER 1 m Setting Up a Composite of 1 07 In contrast D 3 D 5 and D 5 HD are newer digital formats developed by Panasonic D 5 HD supports common HDTV resolutions and frame rates NTSC and PAL DV DV has been the standard for SDTV consumer digital video cap ture since the mid 1990s The NSTC version is 720x480 with a PAR of 0 9 PAL DV is identical to PAL D1 NTSC and PAL 16 9 Widescreen variations of D1 and DV are commonly called 16 9 The res
56. s of nodes within the layered timeline Our goal is to have the best of both worlds Additional Resources The Full Interview To read the full interview with Michael Coleman see the Interviews folder on the DVD Interview Richard Shackleton The Foundry London Richard Shackleton graduated from the Imperial College of Science Technology and Medicine in London with a degree in software engineering He began his career at Nortel Networks and Avid Technology where he special ized in software development for the visual effects and editing markets Richard joined The Foundry in 1999 but left to work with Digital Vision He returned to The Foundry in 2008 and now serves as product manager for Nuke The Foundry was founded in 1996 by Bruno Nicoletti and Simon Robinson The company developed the Tinder plug in set for Flame and went on to create a wide range of tools for all the major compositing pack ages At present The Foundry is a leading developer of visual effects and image processing technologies for film and video postproduction Richard Shackleton 38 CHAPTER 1 m Setting Up a Composite Nuke 5 1 logo LL Nuke was developed in house at Digital Domain Describe the path it took from Hollywood to The Foundry RS Nuke was written as a command line image processing program In 1993 it was used by Digital Domain on the film True Lies The first version which became Nuke 2 was created to read scripts dra
57. t established by the project settings For additional information on the Reformat node see Chapter 5 The tutorial is complete see Figure 1 34 A sample Nuke script is included as nuke1 nk in the Tutorials folder on the DVD 2K_Super_35 full ap Figure 1 33 The initial composite The ouput size is forced to 2048x1556 square tif Read1 symbols_tga aes 1K_Super_35 full ap Figure 1 34 Left The final composite with the proper size of 1024X778 Right The final node network Tips amp Tricks The Crop Node The Crop node in the Transform menu allows you to reduce the resolution of an output by cropping the image edges The Box X Y R and T cells define the left crop edge bottom crop edge right drop edge and top crop edge respectively If the Reformat check box remains unselected the cropped area is rendered black and the frame edges remain unaffected If the Reformat check box is selected the output resolution Is forced to the cropped size 34 CHAPTER 1 m Setting Up a Composite Interview Dorne Huebler Industrial Light amp Magic San Francisco Dorne Huebler graduated from the California Institute of the Arts in 1980 By the time he graduated he was already creating graphics and visual effects for commercials In 1995 he served as visual effects supervisor for James and the Giant Peach Since joining ILM in 1998 he s served as a compositor sequence supervisor and compositing supervisor on such fea
58. the footage name from the Project panel and drop it on top of the layer outline of a composition tab in the Timeline panel For a review of the After Effects interface see the Introduction The layer outline occupies the left side of the Timeline panel Each composition receives its own tab and its own layer outline see Figure 1 11 Once a layer exists in a layer outline it can be selected with the Selection tool If multiple layers exist in a composition you can change their order by selecting a layer and LMB dragging it up or down the layer stack 00001 29 97 fps PERSP ERDOEE PPE SPOSSE REESE Figure 1 11 Left Three compositions and the Render Queue receive tabs in the Timeline panel Right The Selection tool The layer outline functions in a similar fashion to the Layers panel within Photoshop By default higher layers occlude lower layers except where the upper layers are transpar ent due to alpha channels The way in which a layer is blended with the layer directly below it is controlled by a blending mode Blending modes are set by RMB clicking the upper layer name and choosing Blending Mode gt mode You can also set the blending mode by clicking the Toggle Switches Modes button at the bottom left of the Timeline panel which reveals Mode menu buttons beside each layer name in the layer outline The layer outline carries a number of additional composition switches layer switches and menus see Figure 1 12
59. to create an appropriately shaped shadow on the background 5 New wing and neck feathers are fit to the body by spline warping and motion tracking CG renders The resulting composite is merged with a CG render of a television and background The final result is color graded Figure 1 2 Five compositing steps used by Click 3X to create a commercial for Sharp Images courtesy of Click 3X Compositing Examples 5 AILV for Spec Commercial Figure 1 3 shows six steps of an After Effects composite created by the author and students at the Art Institute of Las Vegas AILV The composite is one shot of a spec commercial advertising a futuristic copier A spec is a demo used to show filmmaking or animation skills The breakdown is as follows 1 An actress is shot against bluescreen 2 Stock footage of a city is defocused that is blurred in an optically accurate way 3 The bluescreen is removed from the footage of the actress A scaled and transformed copy is given reduced opacity and a blur to emulate a window reflection A texture bitmap is added with low opacity to create the illusion of dirt on the same window 4 A CG render of a pillar is imported 5 A single frame of the bluescreen footage is iso lated The frame is taken into Photoshop color graded and touched up to remove the wrinkles and seams on the tablecloth The frame is imported back into the composite and placed on top of all the other layers
60. torials folder on the DVD 32 CHAPTER 1 m Setting Up a Composite Nuke Tutorial 1 Working with the Reformat Node Working with source footage that possesses different resolutions can lead to formatting and composition problems unless special steps are taken 1 Open Nuke Choose Edit gt Project Settings from the menu bar In the Project Settings property panel set the Full Size Format menu to 1K_Super_35 full ap This creates a project with a resolution of 1024x778 Note that the resolution bears no indication of a PAR In contrast the NTSC format displays a size of 720x486 9 where the 9 is the non square PAR If a PAR is not listed it s assumed to be 1 0 In the Node Graph RMB click and choose Image gt Read In the Read1 node s properties panel browse for symbols tga in the Footage folder on the DVD Select the Premultiplied check box to interpret the alpha channel correctly Connect a viewer to the Read1 node A graphic with five symbols is shown The viewer indicates the size of the graphic by adding a 1024 778 notation to the top right corner of the view frame In this case the graphic is the same size as the project resolution see Figure 1 32 The project resolution is indicated at the lower right corner of the frame 1024 778 ___ 1K_Supes_35 full ap 2K_Super_35 full ap Figure 1 32 Left 1024X778 symbols graphic Right 2048X1556 city photo 3 In the Node Graph RMB click and choose Image gt R
61. transparency 2 A CG render of a city block is imported as a layer 3 A CG robot is imported as a layer Although the render has self shadowing there is limited specularity 4 A specular render pass and decal render pass of the robot are blended with the original robot layer The result is color graded to create greater contrast In addition a new CG ground plane with debris is placed on top m Compositing Examples 3 5 The ground plane layer is color graded to make it lighter In addition a CG female warrior is brought in as a layer At this point it s difficult to see the warrior over the background 6 The warrior layer is color graded A smoke render is sandwiched between the fore ground and the robot A glow render is added to the end of the warrior s weapon 7 Asmoke render is added to the foreground as a top layer CG lasers and starbursts are imported 8 Environmental fog is added to the background to make the foreground characters easier to see The CG buildings are also blurred All the layers are color graded toward a sepia tone and are given artificial film grain and dirt Figure 1 1 Eight compositing steps used by Freestyle Collective to create a network ID for Cartoon Network Images courtesy of Freestyle Collective 4 CHAPTER 1 m Setting Up a Composite Click 3X for Sharp Figure 1 2 shows five steps of a Flame composite created by Aaron Vasquez at Click 3X a motion graphics and visual effects stud
62. trategy and to ensure that After Effects meets our customers needs I spend a lot of time talking with customers It s important that I immerse myself in their concerns from business trends to the gritty details of production workflows The After Effects team takes its inspiration from an understanding of what our customers need Staying close to our customers gives us confidence that every version of After Effects will help our customers be more creative and more productive If we do this one thing and do it well everybody wins LL Over its 15 year history what have been the most significant changes to After Effects MC If you go back and use After Effects 1 0 you can animate your content in nested hier archical high definition compositions but you might spend some time looking for the time line panel That s because it didn t have one The timeline came in version 2 0 and would certainly be one of the more significant early changes Since then I would say that 3D compositing with cameras lights and shadows was a huge leap forward And 32 bit color painting tools and the animation engine for text and shapes have also opened up a universe of creative opportunity AE ADOBE AFTER EFFECTS C53 PROFESSIONAL hipnin adobe conmigothinds ate Patent amp Legal Mating F ile E 1992 D00F Adobe Systems Incorporated and its Licensors All Rights Reserved Pr Patents pending in the US andjor other countries Adobe
63. tures as Harry Potter and the Chamber of Secrets The Chronicles of Riddick Hulk Pirates of the Caribbean At World s End and Iron Man Industrial Light amp Magic ILM was founded 1975 in by George Lucas as a means to create the special effects for Star Wars The stu dio has since gone on to become a powerhouse in the visual effects industry garnering multiple Academy Awards and a long list of top grossing feature films ILM pioneered many of the com puter animation and filmmaking technologies taken for granted today including 24 fps digital video morphing and photo real 3D characters Dorne Huebler at his workstation Note the CRT monitors including one made by SGI A K KI N ES Ay ey a a E A A tf A l A q yg Aa m O ag i s ar 7 t DA mE Wr cya YS D gt Left R2 D2 and a storm trooper stand guard over the lobby Right A statue of Eadweard Muybridge a pioneer of the photographic study of motion watches over the ILM facility ILM moved to the Presidio in 2005 restoring the buildings of an abandoned army hospital Photos courtesy of Industrial Light amp Magic m Interview Dorne Huebler Industrial Light amp Magic San Francisco 35 At the time of this writing ILM was transitioning from Sabre a modified version of Flame Inferno to Nuke LL You ve been involved with visual effects work for close to 30 years long before t
64. ure 1 20 a Both fields continue to exist and are used if the composition is rendered with interlacing You can force interlacing on the render Figure 1 19 Interlaced footage identified by by changing the Field Render menu in the Render Settings dialog the word Separating in the Project panel 22 CHAPTER 1 m Setting Up a Composite box to Upper Field First or Lower Field First the field dominance should match the intended output format During the render the program creates the appropriate interlacing Note that the interlacing will be successful only if QuickTime Movie AVI Video For Windows or Windows Media is selected as the output format if you choose to render an image sequence the fields are combined without averaging or interpolation On the other hand if a field separated composition is not rendered with interlacing half the information for each frame is discarded and the final image quality may suffer particularly if you re using low resolution footage for the project You can mix and match field separated and progressive frame footage in a composition with no penalty although you should take care when you set up a render through the Render Queue the render will convert field separated footage into progressive frames or the render will convert progressive frames into interlaced fields Ne gi iy Figure 1 20 Left Close up of model lifting a water bottle The dominant upper field as seen in the viewer of the
65. w and show data flow down the tree It was used for Titanic and the T2 3D ride along with many other films Nuke 4 was the first commercially avail able version from the newly formed D2 Software in 2002 Selling commercial software is outside Digital Domain s core interests Both Digital Domain and The Foundry real ized that Nuke could have far greater potential if it was developed and marketed by The Foundry Today The Foundry owns the Nuke IP intellectual property Digital Domain remains one of The Foundry s most important customers LL Nuke is node based What is the greatest advantage of a node based system over a layer based system Are there times when a node based system is a disadvantage RS A node based system allows you to change earlier operations without having to repeat the later steps manually It also allows a free flow of operations whereas a layer based sys tem will direct an artist s approach to working with a particular application model Such freedom in constructing the flow of data and operations promotes many advantages such as intermediate result reuse the creation of operation templates more creative and powerful use of scripting and expressions 3D data flows and nonimage data use A disadvantage is that the program actually does allow such flexibility and may repeat the later steps for you so this can be slower when you change a step other than the last one A layer based system can support a
66. working with interlaced footage Nevertheless the ability of both programs to work with interlacing is discussed later in this chapter Setting Up a Composite After Effects and Nuke each require a unique set of steps for creating a new project import ing footage previewing composites and rendering the result After Effects Projects After Effects composites are referred to as compositions Multiple compositions can exist in a single project To create a new project choose File gt New gt New Project To adjust the project s global properties choose File gt Project Settings In the Project Settings dialog Display Style box you can choose the timeline measurement Timecode Base auto El by switching between the Display Style radio but tons Figure 1 8 If you are working exclusively ieee Drop Frame 7 with video footage the default Timecode Base f Frames radio button is suitable In this case the timeline Feet Frames 35mm uses base 25 or base 30 measurements that is the time is counted in units of 25 frames for PAL and 30 frames for NTSC If you are work Figure 1 8 The Display Style section of ing with motion picture film or CG it s generally the Project Settings dialog box best to select the Frames radio button whereby the frames are counted upward from 1 For the tutorials in this book the Display Style is set to Frames The Project Settings dialog box also carries settings for bit depth an
67. you must connect two nodes to the active viewer Once the nodes are connected select each node name from the A and B drop down menus in the Viewer pane Change the Combine A And B menu to Wipe A wipe handle appears in the viewer You can interactively LMB drag the handle left or right to change the screen split between the two outputs You can adjust the opacity of node B by LMB dragging the handle s diagional arm A Headle wipe B HeadZe r Figure 1 28 Two outputs are split by a wipe handle 28 CHAPTER 1 m Setting Up a Composite Region Of Interest when toggled on creates a region box in the viewer Updates occur only within the region box You can alter the size of the box by LMB dragging the box edges To reposition the box LMB drag the center crosshair Pause when toggled on prevents the viewer from updating even when the node net work is updated or parameter values are changed Update when clicked forces an update even if the Pause button is toggled on Cliptest when toggled on applies zebra stripes to any part of the output that exceeds an RGB value of 1 1 1 Playing the Timeline and Creating a Flipbook There are two ways to test a composite over time within Nuke play back the timeline or create a Flipbook To play back the timeline use the time controls in the Viewer pane As the timeline is played each frame is composited and stored in cache Once all the frames are composited the timeline is able

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