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(DBS) Manual - Initial Set Up

1. 27 08 05 07 01 PM dbs autoguider v4 http www mso anu edu au observing 2 3m DBS autoguider_manual db m x x For Help press F TSE 5x 1 j F Maxlm has excellent features for combining tricolour images The programme knows about centroids rotation and XY shift allows colour adjustment of both foreground and background and has a colour pickup feature for repairing hot colums and pixels See the Maxim help files for description of these features Observers using this feature should copy their source files to their personal areas on data misty then access them and save the resulting colour images from the M23Guider PC back to data misty 15 In case of Software PC or power failure Both the M23Guider PC and the Apogee boost box are connected to no break power supplies and should not normally fail even during extended mains power failures The Maxlm programme can be closed down at any time and re started by double clicking on the Maxlm icon on the Win NTdesktop The M23Guider PC runs Microsoft VVinNT4 operating system and should like UNIX never need power cycling of the PC The NT4 kernel normally continues even when an application programme freezes To stop a frozen programme press Ctrl Alt Delete and select task manager Under the task manager press the applications tab button locate and highlight the programme that is not responding and press the end task button You can then re start the application Maxlm stores
2. DBS Trouble Shooting Guide http www mso anu edu au observing 2 3m DBS dbs_trouble html serv worthwhile at the expense of observing e Aborting exposures part way through See Known problems page Xgterm graphics screen colours not set up If all the colours in the gterm window are the same so that your IRAF plots are invisible you need to set up your Xdefaults In your home directory edit the file xdefaults First check the end of xdefaults Some accounts have been set up with default colours that gterm does not like If they exist comment out the following lines with an V n qmul aq r Black roregrounds black Background d700d700ae00 Foreground fcc00cf007f00 BorderColorF Black Now 1ssue the command xrdb Xdefaults to update the new settings and restart IRAF in a new xgterm If the above does not help or you still do not like the colours add lines such as Gterm color0 darkslategrey Gterm colorl linen Gterm color2 red Gterm color3 green Oterm color4 blue xGterm color5 Cyan Gterm color6 yellow eterm color purple Gterm color8 magenta Gterm color9 slategray Gterm Background white Gterm Foreground black and then re run xrdb as above Last modified August 10 2005 3 of 3 27 08 05 07 37 PM DBS Setting Up Guide http www mso anu edu au observing 2 3m DBS dbs_setup html 1 of 2 Setting up the DBS ready for observations Important Notes The DBS must be at par
3. Disclaimer Privacy Contact ANU Page last updated 09 August 2005 Please direct all enquiries to Webmaster Page authorised by Director RSAA The Australian National University CRICOS Provider Number 00120C 27 08 05 07 04 PM DBS Dichroics http www mso anu edu au observing 2 3m DBS dbs_dichroics html SSO 2 3m DBS Dichroics These data were obtained by comparing the flux reaching the CCD from a standard star with that when using no dichroic or the mirror for the red and blue arms respectively Thus the effects of grating optics and CCD efficiency should all have been removed One residual factor which has not been corrected for 1s the polarisation of light passing through the dichroic The gratings efficiency in polarised light is thought to possibly explain the apparent low throughput in the red This is currently under investigation Please Note In interpretting these data it is important to remember e They were obtained in good but not ideally photometric conditions so the normalisation is arbitary e The blue curves are not absolute but are with respect to the mirror which may contain features of its own Single page summary of the five dichroics Large Gif version of the above plot Postscript version of the above plot Separate plots of each individual dichroic Notes on table Dichroic names are defined by the number on the cell in which they are mounted They do not relate to the manufacturer s na
4. Aperture plates give the DBS a multiplex gain of up to 20 for compact sources Up to 6 arc min and are well worth the extra effort involved in cutting the plates The DBS slithead turret will carry five aperture plates at a time and these should be loaded early in the afternooon See the DBS manual for instructions ensure that you follow the safety instruction and use the black velvet board as plates and bezel rings can easially be dropped onto the blue grating Our current best estimiate for the telescope focal plane scale at the aperture plate is 0 20143mm arc sec The current mask cutting machine covers a circle 72mm in diameter in the centre of the 6mm diameter plate The aperture plate shown here has a mix of 2 arc sec holes and slots for sky background subtraction Ensure that your plates are labled with your object your name and that the viewing side is marked There are three reflections in the telescope so the aperture pattern is flipped with respect to the sky Note the key slot at the top of the plate the dispersion direction is vertical from the key slot through the centre of the plate Aperture plates have the viewing side lightly polished parallel to the slit with fine sandpaper to enhance scatter into the guider optics The plates are viewed from the telescope side of the DBS i e The polished viewing side is inserted into the the slithed turret facing the telescope NOC 20041 STefan Keller faza sim om T iud 10 of 13 27 08
5. The Teldocs Consortium Saskia Besier Mike Bessell Michelle Buxton Paul Francis Ken Freeman Lisa Germany David Hoadley Helen Johnston Lisa Kewley Joe Liske Sean Ryan Elaine Sadler Raylee Stathakis Wilfred Walsh Last modified Tue Jan 25 12 48 07 EST 2000 27 08 05 06 55 PM DBS Instrument Capabilities http www mso anu edu au observing 2 3m DBS dbs_capabilities html 1 of 3 Instrument capabilities Detectors CCDs currently in use e Autoguider CCD D7 and CCD D9 were the DBS Blue and Red CCDs respectively till early 2005 The full chips took about 70 seconds to read out but for single object spectroscopy the chip was generally windowed to half of this or less For details of individual devices see the detector lab Gratings Four gratings are available for each arm This table contains approximate figures For more detail see the DBS grating angle calculator Plane mirrors are also available converting the spectrograph into a focal reducer that images the 6 7 arcmin field at f 1 5 Resolution Resolution Range Order Blaze angle A km s A 300B 1 3938 4 5 334 3800 600B 1 6 54 22 1661 1900 1200B 1 14777 LI 84 970 1200B 2 289 49 0 5 401 470 158R 1 3 37 8 1 337 7150 316R 1 6 48 4 1 1711 3600 600R 1 13 00 22 921 1900 1200R 1 269 45 1 1 451 950 All gratings give dispersions of approximately two pixels per resolution element Dichroics Five different dichroics are available fo
6. Three green indicators BUILDING DRIVE READY AUXILIARY SYSTEMS READY and SERVOS READY should appear A red FAULT indicator or less than three green READY lamps indicates a malfunction which will prevent you observing See the trouble shooting guide At this stage one can if desired open the building shutter the primary mirror cover and start the ventilation fans Always ensure that the mirror cover is fully closed before opening or closing the building shutter This will prevent any detritus from the shutters falling onto the mirror e The telescope control computer is called MATA To log on press BREAK at the telescope control keyboard Username is TELESCOPE For passvvord see the technical staff Unless you have your own account on MAIA enter VISITOR when prompted Please enter Observer s identification Type startup at the s prompt and wait until the TEL prompt appears e The current setup can be shown by entering TEL DISPLAY CONFIGURATION To return to the observer s display use the command TEL DISPLAY e If you have your own account on MAIA load your telescope control file using the command TEL CFILE your filename Otherwise the setup may be changed by entering individual configuration commands e g TEL CONFIGURE FOCAL STATION NASMYTH A TEL CONFIGURE FOCUS CONTROL COMPENSATED TEL CONFIGURE ROTATOR REFERENCE POSITION ANGLE TEL CONFIGURE ROTATOR ORIENTATION SLIT 27 08 05 07 10 PM DBS Observers Guide ht
7. 05 07 01 PM dbs autoguider v4 http www mso anu edu au observing 2 3m DBS autoguider_manual db 11 of 13 VIE wIIIL ILE At dusk after focusing the telescope begin observing at the DBS control computer by inserting and aperture plate and switching on the back illuminator Now take exposures with the MaxIm expose tab and set suitable sub frames set identical sub frame values under the expose and guide tabs This sub frame is usually taller than that used for slit guiding as the aperture plates extend vertically beyond the slit field The holes slowly go out of focus as they depart vertically from the slit line this effect is due to focal reducer viewing the plate at an oblique angle 20 degrees the plate is normal to the telescope axis and does not see any degradation of the aperture plate performance R Ya in Now use the guide expose tab to take a bias frame save this image as bias then slide the frame to one corner of the screen but do not close it you will re use this frame with each new observation Again use the guide expose tab to take an image of the back illuminated aperture plate save this image as plate leave this image on the screen Now set the telescope to the object and the instrument rotator to the correct position angle and use the Maxim expose tab and take a deep image The object is imaged in scattered light from the polished surface of the aperture plate so exposures are normally long typically 60 90 seconds O
8. 512x584 pixels http www mso anu edu au observing 2 3m DBS angle_dial jpg 1 of 1 27 08 05 07 46 PM angle git G F Image 500x307 pixels http Www mso anu edu au observing 2 2m DB angle gif Blue Red 40 1200 G mm Il 35 1200 Gmm 25 i 3 20 oD mom 10 300 Gimm 5 xo xi mous 300 400 500 600 700 800 900 Wavelength nm Double Beam Spectrograph Grating Settings 1 of 1 27 08 05 07 47 PM focus_dial jpg JPEG Image 512x384 pixels http www mso anu edu au observing 2 3m DBS focus_dial jpg 1 of 1 27 08 05 07 48 PM DBS Data Reduction http www mso anu edu au observing 2 3m DBS dbs_reduction html 1 of 1 Data Reduction For a general description of CCD and spectroscopic data reduction see the IRAF data reduction guides For example A User s Guide to Reducing Slit Spectra with IRAF by Massey Valdes amp Barnes Other possibilities do of course exist such as IDL astronomy libraries and Figaro See also Chris Tinney s Figaro extentions Automated DBS data reduction An automated reduction script for IRAF has been written and made publicly available by Lisa Kewley It is well documented and should work fine but is currently offered as is with no warrantee or user support e The cl script e Postscript user manual The link above is the latest version of Lisa s Script It 1s required for IRAF v 2 11 If you are running an older
9. See section on gratings Last modified Wed July 20 2004 by Marilena Salvo 27 08 05 06 57 PM ANU Research School of Astronomy and Astrophysics Detectors 1of2 Research Technology Study RSAA r Observing Telescope Schedules Applying for Time Observing Capabilities Telescopes Detectors Current Info 2 3m Imager DBS Blue DBS Red WiFeS WFI SkyMapper FPA Useful Links Misc Systems Computer Accounts CICADA Travel amp Tourist info SSO Accommodation Booking Support amp Reports Gemini News Jobs Quick Links b RSAA People Contacts RSAA Alumni Public Information Public nformation Hovv to Adopt a Star Stromlo History Book Picture Gallery VVhafs On ntranet Webmail Administration Committees Colloqula amp FoF Computing Library Staff Student Guides Social Timesheets Local Picture Gallery Weekly Bulletins http msowww anu edu au observing detectors index php ANU Home Search ANU Directories Technologu RSAA Detector Scientists and Engineers work with optical and infrared detectors for instrumentation on RSAA telescopes as well as instrumentation fo the largest telescopes to which Australian astronomers have access Use the links at the left to find out more information about the detectors current in use on RSAA telescopes such as the new 2 3m Imager and the up grades taking place with the Double Beam Spectrograph DBS In
10. cold for the next Observer Check with technical staff e TAKE BIAS FRAMES AND DOME FLATS IN THE AFTERNOON to check that the system is working so that 1f you have any trouble the technical staff will be on hand to help You should plan to start setting up for your nights observing in the afternoon before observing at a bare minimum This will allow you to contact the technical staff to help you before they leave for the day Changing DBS Hardware Ensure you have the correct dichroic installed Changing Dichroics The DBS must be at vertical park before removing or changing the dichroic Ensure you have the correct gratings installed Changing Gratings The DBS must be at horizontal park before removing or changing the grating e Set the required grating angle The controls for grating angle are above and below the spectrograph and can be awkward to reach Release the smaller grating lock before attempting to change the grating angle Securely engage the grating lock afterwards but do not over tighten Focus the spectrograph collimators This is most easily done on an arc spectrum The focus dials are similar to the grating angle dials Release the lock before moving the focus and gently secure it again afterwards Login as yourself at console mouldy for DBS red mallorn from moist for DBS Blue start cicada and run teldisk from the Utilities menu to clean up data area and create your own subdirectory Data will b
11. data for yourself on your observing run please pass it on to me for inclusion herein Melles Griot ND Filters These filters lie in the main beam of the spectrograph and hence affect both the science CCDs and the autoguider We have measured optical density plots for all the Melles Griot ND filters but they only cover the range 2000 7000A They will hopefully be made available on line at some later date in the In Laboratory column below Plots from the In DBS column are simply the ratio of the observed flux of a bright star with and without the filter in the beam Nominal Density Nominal Transmittance Name In Laboratory In DBS 5500A 5500A 96 Optical density Transmittance 4 0 0 01 03 FNO 029 3 0 0 10 03 FNO 027 2 0 1 00 03 FNO 023 1 3 5 01 03 FNQ 019 GIF PS 0 6 25 12 03 FNQ 009 Many thanks to those who contributed to this documentation The Teldocs Consortium Saskia Besier Mike Bessell Michelle Buxton Paul Francis Ken Freeman Lisa Germany David Hoadley Helen Johnston Lisa Kewley Joe Liske Sean Ryan Elaine Sadler Raylee Stathakis Wilfred Walsh Last modified Sat Jan 8 21 13 40 EST 2000 27 08 05 07 07 PM fng019 g1f G F Image 508x450 pixels http Www mso anu edu au observing 2 2m DB Filters fngO019 g1f cCOoo 191910 Waveleneth 2 1 of 1 27 08 05 07 08 PM DBS Observers Guide http www mso anu edu au observing 2 3m DBS dbs_observing html 1 of 5 Observers Guide Details of
12. plate rotate the image by 90 degrees then slide it over the spectra and zoom it to fit The image shown here is a small section of the red arm spectra note the Ha emission and absorption near the left edge of the spectra Only one of the aperture plate holes has not delivered spectra 12 Freezing the shutter Maxim CCD Expose Settings Sequence Focus Inspect Guide Setup r Temperature Control Setpoint Actual New L Guider 40 8 385 40 EX Iv Cooler On AU Na Filters Hier C Go To ambient Tem erature stead Restart Shutdown iris cen 4 Eu n i Cancel Alternate Gain IN File Path C Program FilessDiffraction Limited M asim The mechanical shutter in the Apogee camera has an expected life of about 1 400 000 operations In autoguide mode we would reach this limit in about 1 1 2 years We can extend the life of the shutter considerably by freezing the shutter open during normal autoguiding operations To freeze the shutter press the setup tab then the CCD button A window will open check the freeze shutter option and close the window then return to the guide tab For the very shortest exposures the images will show vertical downward tails on each image but his does not seem to effect normal autoguiding operation Under normal conditions use the shutter for setting up focussing and for taking presentation images then switch to freeze shutter mode for n
13. the normal console button TELS SWITCH MIRROR COVER CLOSED TELS SWITCH MIRROR COVER OPEN It is possible to move the tertiary manually from the Auxillary Systems Cubicle downstairs but this must be regarded as an absolute last resort as it 1s believed to make the problem worse Cannot find cALIBRATE POINTING Star If the star is not visible in the guider check all the usual things like RA dec Epoch filters exposure time Maxim DL display grey scale settings etc and then the following 1 Try exposures of different durations and look at the sky value to ensure light is getting through the system 11 Is the star simply hidden behind the decker 11 At the TCS type TEL CALIBRATE POINTING SHOW to get the current pointing constants Write these down in case changing them just makes things worse You can always reset them to these initial values later with TELS CALIBRATE POINTING XC YC where Xc and Yc are the values you just copied down Compare the values you have to those on the white board in the control room Set the values given for Nasmyth_A on the white board using the above command and try to acquire the star again iv Choose another star in a different part of the sky v If none of the above helps it looks like pointing is a long way off for some reason Select yourself a very bright star and you ll just have to hunt around until you find it DBS control computers Any problems with the DBS control computer should be e
14. the telescope control system may be found in the MSSSO Telescopes Command Reference Manual a hardcopy version of which is stored in the console room Getting going quickly A brief crib sheet covering most of what you have to do every night It is principally intended for those who have used the telescope before Detailed descriptions of how to run the instrument are given below Instrument changes Observatory Staff attach the correct instrument and computers to drive that instrument Talk to them about which computers drive your instrument and discuss any recent changes Grating and dichroic changes focus etc are the observers responsibility New and unexperienced observers must make arrangements to have someone familiarise them with the instrument well in advance of their scheduled run Read the Beginning Your Run section of the Getting going quickly manual Starting up the telescope To ready the telescope for observations the equipment comprising TELESCOPE SYSTEMS must be switched on and the group of computer processes which comprise the TELESCOPE CONTROL PROGRAM must be installed and started e Press CONSOLE ON on the PLANT CONTROL PANEL upper left of console Various indicators will now light on the PLANT CONTROL PANEL and the VDUs will come on When the console is off TELESCOPE SYSTEMS cannot be switched on and nor will the TELESCOPE CONTROL PROGRAM function correctly e Press TELESCOPE SYSTEMS ON on the PLANT CONTROL PANEL
15. A focus of the ANU 2 3m telescope The visible waveband 3200 9000 is split by a dichroic at around 6000 and feeds two essentially similar spectrographs with red and blue optimised detectors respectively The full slit length 1s 6 7arcmin Gratings are available with rulings of 158 to 1200 Ipmm giving dispersions of between 4 and 0 6 A pixel The 1200B grating may be used in second order to give 0 3 A pixel over the range 3200 SOOOA The dichroic may be removed or replaced with a flat mirror allowing the use of either arm independently Other possible instrument configurations include replacement of the slit with a slitlet aperture plate up to thirty objects over 6 arcmin and replacing the gratings with plane mirrors converting the spectrograph into a focal reducer that images the 6 7 arcmin field at f 1 5 Assorted useful numbers The DBS is at Nasmyth A focus Telescope scale is 5 02 mm and the f ratio is 17 9 The unvignetted field of the telescope and slit is 80 mm or 6 7 arcmin The collimator focal length is 2812 mm and the camera focal length is 232 mm The beam is 152 mm The cameras are f 1 5 so the imaging scale is about 1 arcsec mm The camera collimator ratio is 12 and the angle is 32 deg Across dispersion 0 015 pixel 0 91 arcsec References A Dual Beam Nasmyth Spectrograph A W Rodgers P Conroy G Bloxham 1988 PASP 100 626 Get a copy from ADS Many thanks to those who contributed to this documentation
16. ANU Research School of Astronomy and Astrophysics RSAA http Www mso anu edu au observing 2 3m DB ANU Home Search ANU Directories Research School of Astronomy and Astrophysics Mount Stromlo and Siding Spring Observatories Ubserving Research o tudy RSAA The Double Beam Spectrograph at the 2 3m telescope Gemini 77 README Known problems and things of which you should be aware Introduction Instrument Overview Quick Links RSAA People e Instrument capabilities and hardware details Contacts Observing RSAA Alumni e Setup amp configuring the DBS ready for observing Observing Reports Public Information Public nformation Hovv to e Trouble shooting Adopt a Star h Fault meporis otromlo History aut Heporis Book Copying your data to tape Picture Gallery What s On ata reduction e Online resources Local and Links Intranet Webmail Grating angle calculator Adan n DBS Exposure calculator Dota O e DBS Arc atlas Committees Ihe CICADA CCD user interface Useful data for Spectrophotometry Bessell Colloguia amp FoF e Spectrophotometric standard stars ESO Computing Library Acknowledgements Staff Student Guides Social Timesheets Local Picture 57 Detailed Table of Contents VVeekly Bulletins RSAA Grapevine Search RSAA instrument capabilities and hardvvare details _Go Detectors Gratings Dich
17. CCD QEs Slit losses Diego references example tables Slit masks multi object observing The use of aperture plates on the DBS enables access to a 6 6 diameter field Using a 76mm diameter aperture this allows for up to 55 individual objects within this field DBS aperture plates can be constructed easily from a reference image of known plate solution The scale within the focal plane is 4 9640 mm Ensure at least 2 resolution elements exist between each slit aperture i e 0 6mm Slits apertures can be made to any appropriate size appropriate for SSO seeing The use of aperture plates on the DBS has a serious limitation acquisition is made from light off the plate surface that is scattered towards the autoguider camera To overcome this ensure that at least one moderately bright star V 13 1s present within the central 3 x2 visible with the autoguider Place a hole in the aperture plate for this reference star a hole of 1 works well Aperture plates are loaded into the plate turret in the focal plane of the DBS housing Align by first back illuminating the plate and recording the image on the autoguider Then move the image of the reference star to its allotted hole One can track either on the scattered light annulus around the reference star or preferably use the TV slide to the side viewing mirrors 180 on the TV slide More description of this mode of operation are contained in the autoguider manual F 1 5 focal Reducer
18. Focus IY Guide Setup go Seconds Binning Delay s dah aha Subframe Fast Left 428 S wiath 200 Top 400 2 Height 200 Auta Reset Camera Idle Dak V Continuous 5 of 13 27 08 05 07 01 PM dbs autoguider v4 http www mso anu edu au observing 2 3m DBS autoguider_manual db 6 of 13 The focus tab in the MaxIm CCD window allows user or auto selection of a subframe for telescope focussing Press the reset button then the expose button then abort the cycle after the first exposure Now pressing the auto button will place a 64x64 pixel box around the brightest star in field If the continuous box is checked the focus command will continue until the abort button is pressed Use the focus tab to set a sub frame and continuously cycle the camera if you intend to hand guide the telescope Ensure you have the telescope guide buttons set to slit co ordinates 6 Inspecting Focus ii Maxim CCD Camera Idle bay 14 FWHM 7 18 Half Flux 7 28 Once focus command is running press the inspect tab before you begin focussing the telescope The inspect tab will display all of the necessary information you need to focus the telescope including the FWHM in pixels and the amplitude The CCD scale is 4 pixels arc sec Focus the telescope for minimum FWHM and maximum amplitude This Maxlm feature is of little use in poor seeing The 3D graph of the star ima
19. IGURE FOCUS CONTROL COMPENSATED TEL CONFIGURE ROTATOR REFERENCE POSITION ANGLE TEL CONFIGURE ROTATOR ORIENTATION SLIT See MSSSO Telescopes Command Reference Manual a hardcopy of vvhich 1s stored in the console room e Open communications with DBS autoguider hardware by typing TELS ENLIST TXA6 Lights within the building are controlled by two lighting switches at the top centre of the console Set to FLUOROS OFF and INCAND OFF or INCAND PRESET e itis safe to do so open the building shutter Press BUILDING SHUTTER OPEN on the console Always ensure that the mirror cover is fully closed before opening or closing the building shutter to avoid debris to fall on the mirror To start the building ventilation fans press VENTILATION FANS ON on the console e Open the mirror cover MIRROR COVER OPEN on the console e Calibrate telescope pointing To set the default DBS aperture send the telescope to a known star s position mag 4 8 and type TEL APERTURE 1 Looking on the autoguider display move the telescope to place the star at the slit centre in line with the decker type TEL CALIBRATE APERTURE More sophisticated calibration options with custom apertures can be performed Focus the telescope by using the autoguider camera as a TV display while driving the focus controls manually See the autoguider manual sections 5 amp 6 Taking Exposures DBS control PC Computer control of DBS hardware such as slit widt
20. IRAF you may need a copy of the previous version Here are the script and the user manual DBS Arc Atlas Last modified Thu Mar 23 11 51 58 EST 2000 27 08 05 08 18 PM
21. N pd bul 1 Checking the camera A Maxim CCD Tx Expose Settings Sequence Focus Inspect Guide Setup cep Apogee 8 Gelip Cooler Regulating a Setpoint 330 Temp 371 r 2 CTI Pg 2 of 13 27 08 05 07 01 PM dbs autoguider v4 http www mso anu edu au observing 2 3m DBS autoguider_manual db 3 of 13 Autoguider SE R G ler When you sit down at the guider control PC called M23guider near the 2 3m console you should find the PC running and Maxlm running f you cannot find the Maxlm window it may be hidden on the task bar which can usually be found by moving the mouse pointer to the top or bottom of the screen When you finish observing please leave Maxlm and the camera thermoelectric cooler running the TE cooler consumes little power and we would like to minimize temperature cycling of the CCD Same as main camera e Note when autoguiding using the Imager on NASB the control PC is M23Imguider Both M23guider and M23Imguider PC s are controlled by a Blackbox Serv Svvitch located in the main telescope console see photo below To switch between PC s either press the appropriate button located on the Serv switch 1 for NASA M23guider PC 5 for NASB M23Imguider PC or else simply press and release the control key on the keyboard then type the appropriate number for the PC you reguire to access BLALA BUA SEMI NI There is a bu
22. S Blue and Imager The workstation mallorn is in the Peripherals room You can log on it from the workstation moist located next to mouldy The Astromed s command structure 1s rather obscure so the CCDs are controlled via a collection of macros which have been predefined and are loaded automatically on the CICADA interface To start type cicada amp in any window of the appropriate workstation and select CCD11 DBS Blue on moist and CCD9 DBS Red on mouldy Set the data frame number using CICADA Numbers of up to four digits may be used In order that the correct header information be read from telescope control computer the exposure must be started on the red arm of the spectrograph before starting the blue exposure IMPORTANT the DBS Imager setup PC does not interact with CICADA therefore whatever information appears there slit width filters lamps used must be entered in the header MANUALLY using CICADA or recorded in your personal observing logbook logfile At the end of the night CCDs should be left on CCD temp flush Select the appropriate macro from the CICADA pulldown menu The controllers are initialised using the Initialise CCD Hardware button on the CICADA menu This should be done at the beginning of the run and every time the bias level counts are abnormal DBS Hardware control Computer control of DBS hardware such as slit width decker and arc lamps is from the PC labelled Imager DBS at the very lef
23. Tertiary mirror Cannot find CALIBRATE POINTING Star DBS problems DBS control computer Autoguider not working Stars look very dim on autoguider CCD problems Excessive noise in image or obvious bias structure HWINIT Aborting exposures part way through See Known problems page Software problems Xgterm graphics screen colours not set up SERVO FAULT or BUILDING DRIVE FAULT lamps at startup If the SERVO FAULT lamp is lit press SERVO FAULT RESET to attempt to clear it If the BUILDING DRIVE FAULT lamp is lit press TELESCOPE SYSTEMS OFF BUILDING DRIVE RESET and then TELESCOPE SYSTEMS ON Even if it is not possible to clear the fault s continue startup anyway and later run the DIAGNOSE program to gain further information In most cases this will inform the observer of the nature of the fault and the subsequent course of action e Running DIAGNOSE The telescope systems diagnostic program called DIAGNOSE 1s run automatically at startup It can be run at any time by entering the command TEL DIAGNOSE This program tests the various status bits and information signalled to the computer by the TELESCOPE SYSTEMS and reports any malfunction or abnormality it finds If faults exist it issues appropriate error messages and often suggests action to be taken by the observer with message in brightened text Finally it concludes with a summary of the telescope state displayed in inverse video It will be one of the following Test seq
24. ach image window and stretch it a little so that the image does not jump off the screen when the zoom functions are used Get used to using the left image window with the expose tab and the right image window with the guide tab ETTTTITE EN Fie Ek Mew Fyxem Lon window heb izimi Jie ola lal ola ox il 27 Aale B e Sequence Focus Ingea Telar iil B fus oce Time fy risen roe Ee h n p 2 T Sequence Mangre Made iraran zl Kalbal atem hecan n Processes Ferlwmancn CPi EFU aspe Hilny 27 08 05 07 01 PM dbs autoguider v4 http www mso anu edu au observing 2 3m DBS autoguider_manual db Having used the track or move command to drag the star into the slit now press the auto button near the guide star co ordinates MaxIm will now automatically find the brightest object in the field and place its co ordinates in the guide star box Now check the track circle and press start Maxim will begin autoguiding on the offset object The in slit object will not be shown in the 32x32 pixel tracking box only the offset guide star The tacking box should be displayed in the right side image window Zoom on this image l Maxim CCD Fi Expose Settings Sequence Facus Inspect Guide Setup C Exposure a Stat C Calibrate 1 00 m Track cix EE Reverse X LN Iv View G
25. acro 15 on menu tablet and then make a horizontal cross section plot through the arc image macro 5 to ensure the stronger lines are not saturated Sample exposures with 2arcsec slit 300B 600B 12008 1200B II 158R 316R 600R 1200R NeAr 10 30 1 1 CuAr 10 30 1 1 FeAr 10 30 1 1 CuHe 10 30 1 1 Quartz 1 3 1 Quartz 2 3 1 Note When using the low resolution gratings the arc lamps are likely to be too bright for even a 1 second exposure You will need to use the arc lamp neutral density filter Starting from the fully transparent position 1 e display reading Rev Limit drive the filter in using the gt button for about 4 6 seconds This should be sufficient to allow a 1 second exposure without saturation You will also have to increase the blue arm exposure to compensate The QI2 lamp 1s slightly fainter than QII so may be better if you find your flats saturating at 1 second You may also find the DBS arc atlas useful Taking flat fields Ouartz lamps Dome flats Twilights Several types of flat field image are possible Two internal guartz lamps are available in place of the normal comparison arcs Some observers have reported finding dome flats more effective except in the UV Ouartz lamps Two separate but similar lamps are available in the arc lamp assembly They are selected through the DBS control computer Without using filters they are rather bright and can saturate the red CCD in less than one second at lo
26. addition work is in hand to provide a new instrument to replace the DBS WiFeS a new double beam Wide Field Spectrograph Finally we are currently in the advanced stages of placing a contract with E2V Ltd Chelmsford UK for a suite of 32 2kx4k for the new SkyMapper telescope being built at Siding Spring The Detector Lab is currently working on detector systems for NIFS Near Infrared Integral Field Spectrograph for Gemini North e GSAOI Gemini South Adaptive Optics Imager for Gemini South e SkyMapper RSAA s newest telescope You can contact the Detector Lab Engineers by sending us an email 27 08 05 07 00 PM ANU Research School of Astronomy and Astrophysics Detectors http msowww anu edu au observing detectors index php RSAA Grapevine Search RSAA E Copyright Disclaimer Privacy Contact ANU Page last updated 25 November 2004 Please direct all enquiries to Webmaster Page authorised by Director RSAA The Australian National University CRICOS Provider Number 00120C 2012 27 08 05 07 00 PM dbs autoguider v4 http www mso anu edu au observing 2 3m DBS autoguider_manual db Users Guide To the DBS and Imager Autoguider System Version 4 June 2004 Peter Conroy Winston Campbell amp John Goodyear Pi E Lm nme dmi Pow yriant Sen eet Lu N pH Cooler i sum gm mh ng the a Lk ru 1 of 13 27 08 05 07 01 PM dbs autoguider v4 http ww
27. all settings during use and will normally re start with your selected settings intact 17 AP47p Trigger Function Both cameras have an external trigger function which can be enabled by the Maxim software The purpose of the external trigger is mainly to prevent accidental exposures during telescope slewing To enable this external trigger function navigate to the setup window from the Maxim CCD control box Click on disconnect CCD This should then allow you to click on the setup button for the Maxim CCD camera You can activate the external trigger function via the External Trigger combo box Setup Apogee Apogee Driver Version 3 04 m Copyright c 2000 2001 Diffraction Limited Technical support supportidap qee ced corn Camera Model Initialization File Path C Program Files Diffraction Limited Maslm DL Apa Browse Shutter External Trigger Priority Level Normal OFF Normal 13 of 13 27 08 05 07 01 PM ANU Research School of Astronomy and Astrophysics RSAA 1 of 3 Research Technology Study RSAA Observing Telescope Schedules Applying for Time Observing Capabilities Telescopes Detectors s Current Info 2 3m Imager DBS Blue DBS Red WiFeS WFI SkyMapper FPA Useful Links Misc Systems Computer Accounts CICADA Travel amp Tourist info SSO Accommodation Booking Support amp Reports Gemini News Jobs Quick Links RSAA Pe
28. arc mirror is IN If the arc lamp is too bright neutral density filters are available See Changing filters above Taking calibration data Bias Frames The repeatable bias structure 1s small typically 1 in B and 3 in R The bias level is of order 1000 so simple consideration of the Poisson statistics shows that you need gt gt 10 bias frames to really measure it properly Do not mistake random noise which often appears for genuine bias structure Using too few biases which include random rubbish will make you data worse not better The CCD controller sometimes creates considerable noise in the form of coarse horizontal striping which cannot be corrected by bias frames it looks a little like a badly tuned TV signal This must be cleared by running Initialise CCD Hardware from the Cicada pull down menus but this also resets the bias levels rendering the old bias frames unreliable ld n hi Td k Er a Ft AF An example 4177 of an R bias frame o Arc lamps for wavelength calibration NeAr CuAr FeAr and CuHe arc lamps are available The CuHe lamp actually appears to be CuHeAr The blue end of the spectrum 1s certainly dominated by Argon lines To switch arcs on see Selecting arc lamps above 27 08 05 07 10 PM DBS Observers Guide http www mso anu edu au observing 2 3m DBS dbs_observing html 4 of 5 When choosing an appropriate exposure time it is helpful to run Autoscale and Update Display m
29. asily fixed by closing down the control programme with the FILE EXIT menu and restarting it Should the PC itself need to be rebooted it 1s located in the DBS electronics rack on the Nasmyth platform Autoguider not working If the autoguider does not appear to be moving the telescope Have you run ENLIST TXA6 On the TCS Do you have only one copy of MaxImDL running on the PC If the answer to both of the above 1s yes close down MaxImDL close down any other applications running on the PC and restart the auto guider software as per instructions in the auto guider manual If this does not help re read the auto guider manual in detail e Stars look very dim on autoguider If you can only find very bright objects in the autoguider or nothing at all Check the TV filter in the DBS hardware control 1s set to CLEAR If it is select another filter setting and return it to CLEAR again to make sure the display is updating correctly Excessive noise in image or obvious bias structure HWINIT The CCD controller sometimes creates considerable noise in the form of coarse horizontal striping which cannot be corrected by bias frames It looks a little like a badly tuned TV signal It is normally cleared by resetting the ASTROMED controllers with the Initialise CCD Hardware option in the CICADA pull down menu The bias structure is usually not sufficient to make running new bias frames in the middle of the night 27 08 05 07 37 PM
30. d saving images on the XP platform make yourself a directory on the Explorer D drive to store data Please erase this account when you finish observing To connect and make your area on the unix data disk data moistl cicada _user_ accessible as a drive from the autoguider PC 1 Open the Windows Explorer if it is not already open by right clicking on the start button 2 Choose Map Network Drive from the Tools menu If this share already exists remove the Mapping 4 of 13 27 08 05 07 01 PM dbs autoguider v4 http www mso anu edu au observing 2 3m DBS autoguider_manual db Map Network Drive Windows can help you connect to a shared network Folder and assign a drive letter to the connection so that you can access the Folder using My Computer Specify the drive letter For the connection and the folder that ynu want fo connect E R TRE BE RE RE RR RE BOO RE BE RE RE RE R ov TEDD Felder Wnurkyldata moist1 v Browse Example serverishare Reconnect at logon Connect using a different user name Sign up Far online storage or connect to a network server urma 3 Select a drive letter U for UNIX is a possible choice 4 Type the share name as WnurkyMata moistl 5 Put your personal Unix username in the Connect As box 6 Turn Reconnect at Logon to OFF 7 Enter your personal Unix password when prompted 8 Use Disconnect network link to break the link when you
31. e stored in this subdirectory called e g data mouldy cicada jsmith for the user jsmith using the DBS Red running on mouldy Start Of The Night Start telescope e At main console press buttons CONSOLE ON and TELESCOPE SYSTEMS ON If the SERVO FAULT lamp is lit press OFF and then SERVO FAULT RESET to attempt to clear it If the BUILDING DRIVE FAULT lamp is lit press TELESCOPE SYSTEMS OFF BUILDING DRIVE RESET and then TELESCOPE SYSTEMS ON If this does not clear the fault s continue startup anyway and later run the DIAGNOSE program to gain further information The telescope control computer is called MAIA Tolog on press BREAK at the telescope control keyboard Username is TELESCOPE For password see the technical staff Unless you have your own account on MAIA enter VISITOR when prompted Please enter Observer s identification e Type startup at s prompt and wait until the 5 prompt appears The current setup can be shown by entering TEL DISPLAY CONFIGURATION To return to the observer s display use the command TELS DISPLAY e If you have your own account on MAIA load your telescope control file using the command TEL CFILE 27 08 05 07 10 PM DBS Getting Going Ouickly http www mso anu edu au observing 2 3m DBS dbs_getgoing html 2 of 4 your filename Otherwise the setup may be changed by entering individual configuration commands e g TEL CONFIGURE FOCAL STATION NASMYTH A TEL CONF
32. erience you want gt gt 10 bias frames to really measure it properly Do not mistake random noise which often appears for genuine bias structure Using too few biases which include random rubbish will make you data worse not better The CCD controller sometimes creates considerable noise in the form of coarse horizontal striping which cannot be corrected by bias frames It looks a little like a badly tuned TV signal This must be cleared by reinitialising the CCD hardware from the CICADA pulldown menu but this also resets the bias levels rendering the old bias frames unreliable Where To Find Your Data Your data will be in the subdirectory created for you when you ran teldisk and visible through the CICADA Preferences pulldown menu You need to back up your data BEFORE you leave the telescope because your data will be automatically deleted when the next user runs teldisk You can write your data to tape using tar or your favourite data writing command on the tape drive located on mudslide in the Console room However various observers have had problems in reading their tapes written on this drive when they got home Many observers nowadays prefer to back up their data on their personal laptops at the end of their run RSAA does not have an archive of data taken at the 2 3m at this stage therefore all data that has not been properly backed up is lost This page 1S http www mso anu edu au observing 2 3m DBS dbs_getgoing html Las
33. finish observing Note currently Map Network Drive only works on the Win XP Imager AP47p computer as the Connect using a different user name is not available under Win98 We need to change the user name because the autoguider PCs run under the observer account but the network drive must be mapped using the observer s Unix login name Apogee autoguider users can copy finding charts as fits files to their private areas on data moist cicada user before the observing run and view them with Maxlm in a window that can be flipped rotated and zoomed to simultaneously match data being displayed from the DBS slit This works best with finding charts up to 1024x1024 pixels The DBS data can also be viewed in Maxlm once it has been converted to fits and copied to your Unix directory Open both red and blue data frames and flip one vertically Both data panels can be moved around independently and placed end to end to help visually track spectra I you have both data panels and the appropriate finding chart open you can easially locate the objects that produce orphan spectra on the long DBS slit Connecting to the UNIX system will work only if you have a Unix account and the directory data moist cicada user has been created by teldisk There is no longer an account called observer on the UNIX system all data is stored under personal accounts 5 Setting a focus frame Using the camera as a television ZUM Fr Expose Settings Sequence
34. ge auto scales as the telescope is focussed 7 Setting up for autoguiding Autoguider Settings 2 Anis Auto Dark da s iy Enable amp ANS Cancel lw Enable Y Axis Serial Command oy gig 1 TelescopeDec lffset slit More Lal Time Backlash Aggressiveness 3 fi 5 Display Scaling Focal Length mm Pixel Size um Manual Calibration 2000 p 4 M deta A Speed Y Speed Angle deg Display Made Y Piel Size fum ER m 21 5 l Pixels Y p A Kul Exposure Settings Binning Left Top Width Height 3 p fo 4 pe en 4 s Reset 27 08 05 07 01 PM dbs autoguider v4 http www mso anu edu au observing 2 3m DBS autoguider_manual db More Autoguider Settings aricel Minimum Move T sec Move Commands Maximum Move X sec 30 EN Maximum Slew x sec Maximum Move Y sec El EN Maximum Slew Y sec Delay After Correction sec 30 j Delay After Command sec Output Enables Iv Enable Iv Enable Iv Enable 7 Iv Enable 7 Track Log File Mame rack Jog Sele kodel T Enable Log ffset Tracking File Path Ezab Gi At the telescope control computer ensure that the VAX Telescope Control Computer is listening to the autoguider computer by typing lt enlist TXA6 for DBS amp TXA3 for Imager gt Now at the autoguider computer p
35. ght When slit is in position angle 90 the left end of the slit points East Changing filters Whole system A filter wheel located before the slit carries five 48mm neutral density filters They are Melles Griot metal on glass filters and allow approximately 50 10 1 0 1 and 0 01 transmission at 5000A Each filter or a clear aperture may be selected using the Main Filter dialogue box from the M1 window Plots of transmission curves are available for some filters Autoguider Conventional B V and R filters as well as a set of neutral density ND filters are available for the autoguider camera They may be selected from a pop up menu attached to the TV Filter button in the M1 window normally to the left of the screen Arc Lamps A neutral density wedge filter covers the arc lamps to allow them to be dimmed Click on ArcFilter in the M1 window to open the control dialogue box The filter is adjusted clicking the on screen gt button to darken it and x to lighten For no filtration drive it fully to the left until the display reads RevLimit Selecting arc lamps NeAr CuAr FeAr and CuHe arc lamps and two quartz flat fields are available Only one lamp may be selected at a time and it 1s specified in the Arcs dialogue in the MI window A mirror folds the light from the lamps into the spectrograph and is controlled from the ArcMirror dialogue also in the M1 window The lamps are switched on automatically when the
36. h decker and arc lamps 1s from the PC labelled Hmager DBS at the left hand end of the main console If the DOS prompt is showing run dbs from the dbs directory Then select control status from pull down menus Arc lamps are automatically switched on when the arc mirror is set to IN and switched off when the mirror returned to OUT Check the TV slide is centred value around O Setting up the CCDs The CCDs are run by Astromed controllers on a pair of workstations to the left of the telescope console All interaction with the CCDs is now performed via the CICADA GUI See Taking Exposures for details of their operation When not in use the CCDs should be left on CCD temp flush e To set the CCD read out window use the CICADA pull down menus To check the read out window is correctly centred drive the decker in until it occults part of the slit see The Decker Use the autoguider to watch as you drive the decker in Take an exposure with any lamp and the dark band where the decker obscures the slit should lie at the middle of the defined window The pixel scale is 0 91 arcsec mm Make sure the window has an overscan region at right side of image since any bias structure normally takes the form of horizontal bands Remember the monitor does not display the full 1850 pixel width of the image See Taking Exposures End Of The Night At the telescope control terminal enter TELS PARK When the telescope stops mov
37. he appropriate box in the storage drawer on the accessories trolley e Select the next dichroic and insert it into the beam splitter The handle of the dichroic cell should be downward when facing the beam splitter Ensure that the four thumb screws securing the cell are properly positioned or they will foul the slithead turret If the beam splitter door is to be left open for some time cover the beam splitter with the black velvet bag that hangs on the near end of the accessories trolley In addition a multilayer coated mirror and multilayer coated window are available for use when using the spectrograph as a single armed red or blue instrument Setting the Central Wavelength Grating Angle The grating angle setting assembly consists of three dials The small locking knob should be released before moving the grating and re set once the movement is complete There is a large dial which gives the approximate grating angle and an engraved scale down to the arc minute level on the smaller dial with a handle The blaze angle settings are engraved on the setting wheel To observe away from the blaze angles may be read off this plot They give a good starting point Take an arc and tweak the angle as necessary Alternatively there 1s an accurate online grating angle calculator Collimator Focus Before moving the focus setting dial you must first release the small adjacent locking knob Gently but securely re set the locking knob into place
38. ing TBD Width Slit width range Resolution formulae TBD Length Spatial scale Chip size readout window TBD Decker Spatial resolution Telescope scale is 5 02 mm and the f ratio is 17 9 TBD Determined by seeing guiding spectrograph etc TBD Typical values Filters A filter wheel located before the slit carries five neutral density filters of 48mm diameter and a large clear aperture of 120mm The clear aperture allows unvignetted use of the full 80mm field at the slit The five neutral density filters are Melles Griot metal on glass filters and allow approximately 50 10 1 0 1 and 0 01 transmission at 5000A The 48mm filter diameter restricts the usable slit length to 26mm or 2 2 arcmin Plots of transmission curves are available for some filters For details of the dichroics see above System throughput We do not currently have a full throughput analysis of each separate component but the experimental exposure calculator should tell you what you really need to know 1 e how faint you can go Please note that this version refers to the previous CCDs and controllers therefore the results should only be considered as a broad guideline TO BE DONE Some example data standards 27 08 05 06 57 PM DBS Instrument Capabilities http www mso anu edu au observing 2 3m DBS dbs_capabilities html 3 of 3 Count rates at various magnitudes S N calculator Atmospheric transmission from AAT RGO manual
39. ing enter 27 08 05 07 10 PM DBS Getting Going Ouickly http www mso anu edu au observing 2 3m DBS dbs_getgoing html TELS SHUTDOWN and wait until the system advises that it is safe to leave The mirror cover and building shutter will be closed automatically but should be checked by the observer e Finally you may optionally enter TEL CONSOLE OFF e Restore building lights to normal e Fill dewars 3 of 4 27 08 05 07 10 PM DBS Getting Going Ouickly http www mso anu edu au observing 2 3m DBS dbs_getgoing html 4 of 4 e At the end of your run fill in the online Observer s Report form The Autoguider Acquisition CCD Camera See also the 2 3m autoguider manual The slit is visible in autoguider camera The orientation is reversed by default e g N up E to right When slit is in position angle 90 the left end of the slit points E Note however that the autoguider display has options to flip and rotate the image to any orientation Calibrations For telescope pointing calibration see Start of the night above Flats Some observers have reported dome flats are better than the internal Quartz lamp except in the UV Twilights flats are generally required for correcting the slit illumination in the flats Dark Frames Dark current is small about 0 5 electrons pixel hour so dark frames have not generally been necessary Bias The repeatable bias structure is small typically 1 in B and 3 in R In my exp
40. isplay window grab the lower right corner of the window and stretch the window down and to the right this will prevent the image from jumping off the edge of the monitor when the zoom function is used Qail iki Dime rm ma a sal ril mit 27 08 05 07 01 PM dbs autoguider v4 http www mso anu edu au observing 2 3m DBS autoguider_manual db ei elt a sasi Sorot Fara pos Time m P a bos c Tel Film Salton t Kies ET em Z an T fenem A fully black window may be saturated use the cursor in the image and the information window to ensure that the maximum values are below 65k Use the Histogram window to adjust the displayed grey scale slide the two coloured pointers towards the peak of the graph or swap them over if you like a negative display Fast clicking the right mouse button changes the diameter of the sample circle around the cursor Close the circle around any star in the field and read of the centroid position and FWHM of the star from the Information window Use the zoom buttons or better still the amp keys in the numeric keypad to zoom in the image If the 90400 zoom is to small point in the zoom factor display in the Maxlm button bar and edit this value to between 901000 and 1600 Use the slide bars to pan around the zoomed image or better still place the cursor in the zoomed image press and hold the right mouse button move the mo
41. ken against a dark night sky Twilight fields can be very effective at correcting the flats before they applied to data frames See for example A User s Guide to Reducing Slit Spectra with IRAF by Massey Valdes amp Barnes 27 08 05 07 10 PM DBS Observers Guide http www mso anu edu au observing 2 3m DBS dbs_observing html End of night procedures Shutting down the telescope at the end of the night is largely automated e At the telescope control terminal enter TELS PARK When the telescope stops moving enter TELS SHUTDOWN and wait until the system advises that it 1s safe to leave The mirror cover and building shutter will be closed automatically but should be checked by the observer e Finally you may optionally enter TEL CONSOLE OFF e Restore building lights to normal Remember to fill dewars This page 18 http msowww anu edu au observing 2 3m DBS dbs observing html Last modified Wed August 10 2005 5 of 5 27 08 05 07 10 PM DBS Getting Going Ouickly http www mso anu edu au observing 2 3m DBS dbs_getgoing html 1 of 4 DBS Quickstart Observing Guide Beginning Your Run IMPORTANT Be familiar with the SSO and 2 3m rules Fill the dewars every morning and evening The dewars typically have a 12 hour hold time Check the CCD log book for appropriate times and always fill in the CCD log yourself Remember there may be dewars on the telescope other than the DBS e g the Imager that need to be kept
42. l db From 1139 y 82 Auto T A 135 Y ER Iv Lack Manual Central 7 b Swap x Guider Status Swap 5 pa x Swap Axes i zl Sec Auto Expose Press the guide tab and check the expose circle inside the guide tab Do not confuse this expose circle with the expose tab above it Now press start Maxlm will display a subframe whose size 1s set in the autoguider settings box zoom in on this image Now press the move command button in the lower right corner of the guide tab When the move window opens use the mouse in the zoomed image and pick the from star then press the move button in the move window The to position can be locked to the centre of the slit or just above the slit by pointing in the image then checking the lock option this probably needs to be set only once at the beginning of the observing run If you intend to use in slit guiding make the to position a few pixels above the slit as MaxIm needs to measure the amplitude of the star before autoguiing it into the slit If you are using offset guiding make the to position the centre of the slit The maximum allowable move is 50 arc sec or 100 pixels in x and y P Maxlm will move the telescope and if the auto expose box is checked will take and display another image There is currently an 8 second delay after a move command to allow time for the telescope to settle before the auto ex
43. m needs to measure the peak value of the star before autoguiding it into the slit Maxim will report Guide Star Fade once the star is in the slit and the peak value falls by about 50 and will not transmit tracking commands until the peak value lifts above 50 of the original value If the star is in the slit at the beginning of the guide sequence then Maxlm may attempt to move a relatively faint star that is inside the tracking box into the slit Once the star is in near the slit check the track circle in the guide tab and press start MaxIm will now read up a 32x32 pixel tracking box and begin transmitting correction commands to the telescope control computer Maxlm will pull the star to the RELATIVE co ordinates shown in the guide star box on the lower section of the guide tab window This position can be set by simply pointing at the centre of the slit and pressing the left mouse button When the 32x32 pixel guide window opens zoom into this window and leave the cursor over the guide star in the Autoguider Image window MaxIm will then show the current guide error in arc seconds or pixels in the lower left of the guide tab window and the centroid and FWHM in pixels in the information window There is currently about 1 8 seconds of dead time in the autoguiding cycle 10 Offset autoguiding Jogging the tracking box Setup the Maxlm desktop to show two image windows place the CCD image window on the left and the guide expose window on the right Grab e
44. me speed i e about 15 seconds There is now NO slow or medium speed with the new Imager So the DEFAULT 2 4e adu lod file is fast lod The GAIN setting of the lmager may now be changed using the GAIN option on the Cicada Menu rather than re loading a timimg file lt o o Imaging 13 5um Foy 2048x512 Full 3 Frame Well 4 65 G 3 2148x562 120ke E2V CCD4210 Imaging 13 5um EoV 2048x2048 Full 4 4 Frame Well 3 6 E2V CCD4240 2148x2148 120ke 3 CCD4210 Frame Well 4 65 G 3 2148x562 120ke Imaging 13 5um E2V Foy 2048x512 Full 5 Gz2 ib The gain settings and noise are as follows 27 08 05 07 04 PM ANU Research School of Astronomy and Astrophysics RSAA http msowww anu edu au observing detectors current_info php 3 of 3 GAIN CDS Gain ua Noise e Bias Comment 4 DBSB Timing Files and Gain Settings For the DBSB fast medm slow the detector is read out at the same speed i e about 7 seconds There is now NO slow and medium speed with the new DBSB or DBSR So the DEFAULT 1 04e adu lod file is fast lod However the GAIN setting of the system may be changed according to the table below The gain settings and noise are as follows GAIN cos Gain ua Noise e Bias commen 2 2 1 04 3 5 1230 Default 3 1 2 30 4 65 1241 Low Gain Enquiries about Current Detector Information detman mso anu edu au Copyright
45. ming and in at least one case are different from the numbers given in the original hardcopy manual e Transition gives the approximate wavelength of where transmission reflection e Range 1s the approximate wavelength range over which the transition occurs e Blue limit is the very approximate wavelength where reflection starts to break down This is rather subjective especially for dichroics 4 and 5 If you wish to observe bluewards of this limit you will need to use the mirror and forego any data from the red arm Transition A Name Range Blue limit A Plot Large GIF Postscript 1 of 2 27 08 05 07 06 PM DBS Dichroics http www mso anu edu au observing 2 3m DBS dbs_dichroics html D gif DI D5 5650 1 3300 6150 2 7 3750 D3 7 3750 D3gif D1 D5 D2 gif 01 05 DI D5 E B 6150 4 750 3500 6480 1100 3300 Many thanks to those who contributed to this documentation The Teldocs Consortium Saskia Besier Mike Bessell Michelle Buxton Paul Francis Ken Freeman Lisa Germany David Hoadley Helen Johnston Lisa Kewley Joe Liske Sean Ryan Elaine Sadler Raylee Stathakis Wilfred Walsh 5 gi DI D5 E EO E EL ELE Last modified Tue Jan 25 12 48 07 EST 2000 2012 27 08 05 07 06 PM Arc Atlas 1 of 1 http www mso anu edu au observing 2 3m DBS dbs_filters html SSO 2 3m DBS Filters These data are very far from complete If the plots you require are not here and you obtain the
46. mplemented differential refraction curves Not yet implemented Almanac data sunrise sunset hourly airmass tables seasonal observability etc Acknowledgements Many thanks to those who contributed to this documentation The Teldocs Consortium Tim Axelrod Saskia Besier Mike Bessell Michelle 2 of 3 27 08 05 06 52 PM ANU Research School of Astronomy and Astrophysics RSAA http www mso anu edu au observing 2 3m DBS Buxton Paul Francis Ken Freeman Lisa Germany David Hoadley Helen Johnston Stefan Keller Lisa Kewley Joe Liske Sean Ryan Elaine Sadler Raylee Stathakis Wilfred Walsh Copyright Disclaimer Privacy Contact ANU Page last updated 24 August 2005 Please direct all enquiries to Webmaster Page authorised by Director RSAA The Australian National University CRICOS Provider Number 00120C 3 of 3 27 08 05 06 52 PM DBS Known Problems http www mso anu edu au observing 2 3m DBS dbs_known html 1 of 1 Don t say we didn t warn you There have been changes to the system Much of this document is now being updated The old digitiser tablets have gone as has the need to start red and blue exposures sequentially CCDs are controlled by CICADA See the on line documentation The DBS blue and the Imager are currently controlled via the same workstation mallorn located in the Peripherals Room and accessible by the Observer via the workstations moist and mouldy in the control room Swi
47. nce this exposure is complete and shown on the screen pull down the Colour menu in MaxIm and select Combine Tricolour Make the bias frame blue the back illuminated aperture plate red and the deep sky image green Now select autocombine with no shift or rotation Once the colour image appears pull down the colour menu and use adjust colour balance only the background colours normally need adjusting Now use the move command to move the stars into the red holes Take another deep image if the stars are in the holes a halo may be seen around the some of the brighter stars as shown 1n this thumbnail image Now in the guide tab reduce the exposure time press auto then track then start and MaxIm will begin guiding on the brightest object in the field Peroidically interupt the guiding and take a deep exposure with the expose tab to ensure that the stars are still in the holes It is wise to save some of the images of the aperture plates the colour images can be saved as jpg or tif format 27 08 05 07 01 PM dbs autoguider v4 http www mso anu edu au observing 2 3m DBS autoguider_manual db 12 of 13 Once the DBS exposures are complete and the data has been converted to fits and moved to data misty you the data and aperture plate images can be viewed simultaneously on the PC screen Open both red and blue images together and flip one image vertically so that the spectra have the same end of the slit at the top Then open an image of the aperture
48. nd may be undone by hand If an alarm sounds close the door and correctly park the spectrograph in the horizontal park position e Insert the grating cover into the slot in the grating cell and attach the grating cover handle to the grating cell with the two captive thumb screws e Pull the grating release lever This lever actuates an over centre lock and the lever will rotate through 90 and protrude through the access door aperture when fully open Do not under any circumstances pull the grating release lever if the spectrograph is not in the horizontal park position as the unprotected gratings can slide out of the spectrograph and fall to the floor e Carefully withdraw the grating cell by pulling on the grating cover handle ramps will guide the cell sideways as it is withdrawn support the cell with both hands as it clears the spectrograph body Replace the cell in the storage cabinet and select the next grating e Insert the next grating with the dovetail claws of the cell facing towards the telescope Ramps will guide the cell sideways to engage the dovetail claws Push firmly on the cell handle and while maintaining this force close the grating lock lever Pull gently on the cell handle to ensure that the cell is locked Then undo the two thumb screws withdraw the grating cover and close the grating access door e Store the grating cover in the storage cabinet and if necessary change the grating in the other arm of the spectrograph Retu
49. once the focus is set e The easiest way to focus is take an arc exposure and use the tablet menu to make a horizontal cut through the image Then you have to shuttle up and down stairs moving the focus taking an exposure making a plot and back down to the dome to try a new focus It s in focus when you have the maximum counts in the arc lines and they are at their narrowest Note that changing the focus will move the image on the detector in the spatial direction Bear this is mind when focussing and choosing the read out window e The focus should be around about mm but frequently is not It seems to drift off over time I have had it vary by 50mm from observing run to observing run A minimum change of about 3mm is required to have any noticeable effect on the spectra Taking a sequence of exposures stepping the focus by 5mm at a time seems to be adequately fine to get a good focus Larger steps may be necessary initially to find a rough focus Non negligible astigmatism principally from the spherical collimator causes the best spectral and spatial foci to differ For the blue arm they are separated by 8mm and the red arm by 12mm The extra astigmatism in the red arm is from the beam splitter For some applications e g aperture plates or slitless spectroscopy it may be preferable to use a compromise focus between the two optimal limits Last modified Tue May 30 13 11 59 EST 2000 27 08 05 07 45 PM angle d al jpg JPEG Image
50. ople Contacts RSAA Alumni Public Information Public nformation Hovv to Adopt a Star Stromlo History Book Picture Gallery VVhafs On ntranet Webmail Administration Committees Colloqula amp FoF Computing Library Staff Student Guides Social Timesheets Local Picture Gallery Weekly Bulletins Technologu http msowww anu edu au observing detectors current info php ANU Home Search ANU Directories 27 08 05 07 04 PM ANU Research School of Astronomy and Astrophysics RSAA http msowww anu edu au observing detectors current_info php RSAA Grapevine Search RSAA E yn G 2 of 3 Dewar numbers Dn indicate re furbished heads Detector Dewar Frame Pixel Read Format Size Noise e Details S TE 2k D10 Tek 2048x2048 24um m m q on 40 thinned R O time 7s on 2 3m telescope Nevv DBS B Old Tek 1kx1k thinned R O time 15s on 2 3m telescope Nevv lmager Old EEV 2kx1k thinned R O time 7s on 2 3m telescope Science Detector has been received back at RSAA Commissioning Now expected to be mid Septembei New DBS R Old Tek 1752x532 grade 1 DBS only This 7 7 retired an DBS R D9 SITE 1752x532 15um 5 brought to RSAA and usec for WiFeS CCL L O d Jn E2V Imager Timing Files and E2V Imager Timing Files and Gain Settings Settings For the lmager fast medm lt slow the detector is read out at the sa
51. ormal autoguiding 13 Daytime testing To test the autoguider functions during the daytime and practice autoguiding go to the DBS control computer then to the slit turret control and insert the row of holes aperture plate Then switch on the back illuminator This will insert an aperture plate and back illuminate it to create a row of fake stars for the autoguider to work with At the VAX telescope control computer start the telescope control computer type lt enlist TXA6 gt then start the telescope tracking by typing lt track here gt Now at the autoguider computer start the Apogee camera and work down through sections 1 to 11 of this manual When the autoguider sends move or guide commands to the telescope control computer the offsets are updated in the VAX co ordinate display window The DEC offsets are in arc seconds the RA offsets are in sidereal seconds where one sidereal second equals 15 arc seconds Jog the tracking box to one side of a fake star and start autoguiding The star will remain off centre of the tracking box and the offset co ordinates will increment with each tracking cycle Jog the tracking box to the other side of the star and the offsets will decrement with each tracking cycle 14 Image processing Combining images to make colour images IS Maxim DL JN_HORS IET rh firi ombre Tuza N HORSAR jpg a Scaling Factor T Green mage HDR54 G ipa Scaling Factor f
52. pose occurs If the star is near or in the slit close the move box You are now ready to autoguide The move and guide commands use a separate co ordinate frame system from the expose tab focus commands Sub frames set under the guide tab will stay set independent of settings under the expose and focus tab The manual control buttons are useful for moving the star a discrete amount in x and y directions and are especially useful for Nasmyth aperture calibrations Set the reguired manual shift in the manual control entry box in arc sec The maximum manual shift is 50 arc sec or 100 pixels 9 In slit autoguiding li Maxlm CCD EES Expose Settings Sequence Focus Inspect Guide Setup Expose Exposure Declination Calibrate 1 00 4 nh 4 f Track Statue Stop Reversed lle BEN H View Guider Settings Error Y Error Guide Star HE m x 13 y fez k l 8 of 13 27 08 05 07 01 PM dbs autoguider v4 http www mso anu edu au observing 2 3m DBS autoguider_manual db 9 of 13 SUB Maxim CCD Tx Expose Settings Sequence Focus Inspect Guide Setup Expose Exposure Declination ve xte TBBU Pale x Calibrate 1 00 l x g Status Em Revenen fie v View Guider Settings R Error 5 Error Guide star 133 ii 82 E ma Move As noted in Section 9 in slit autoguiding should begin with the star a few pixels above or below the slit as Maxl
53. r the beam splitter Each switches from transmission to reflection at around 6000A though this may be varied over about 1000A depending on your choice of dichroic The transition takes between 400A and 1000A for the various dichroics There 1s a plane mirror labelled D6 on the mounting cell for using the blue arm alone Leaving the beam splitter empty will send all the light to the red arm Although curves for six dichroics appear in the original printed manual the one named D5 in the manual is not currently available in the instrument If for any reason you think you require it contact us well 27 08 05 06 57 PM DBS Instrument Capabilities http www mso anu edu au observing 2 3m DBS dbs_capabilities html 2 of 3 in advance of your observing run Transmission reflection curves have been observationally obtained The small scale features are in good agreement with the manufacturers data but the system sensitivity seems to be very significantly reduced redwards of 7000A for reasons that are currently under investigation Long Slit The unvignetted field of the telescope and slit is 80 mm or 6 7 arcmin The remotely controlled bi parting slit opens to 4mm 20 arcsec with an accuracy of approximately 20micron A remotely driven tapered decker may be used to obscure up the 5mm 25 arcsec at the centre of the slit The entire slit assembly 15 tilted by 10deg allowing a CCD camera to image the reflective slit jaws and 1s used for offset guid
54. ress the guide tab and the settings button to display the autoguider settings window Note that the Manual Calibration settings are X 2 16 and Y 2 16 these are the guider correction speeds in pixels per arc sec Do not change these settings or change the sign of the settings or the guider will force the star out of the tracking box The windows shown here shows typical settings for the autoguider You may wish to change the aggressiveness setting on a scale from 1 to 10 This factor inputs to the simplest possible servo filter a setting of 5 will move the telescope by 5 10 or 1 2 of the calculated error signal a setting of 10 10 will move the telescope by the full error signal Our experience thus far is that the better and more stable the seeing the better the guider performs It is best to set the X Y W H settings to exactly the same values as those shown under the settings tab From time to time the guide calibrate programme will need to be run and should return speeds near X 2 16 and Y 2 16 8 The Move command Pulling a star into the slit b Maxim CCD Expose Settings Sequence Focus Inspect Buide Setup Expose Exposure Declination Calibrate lo Track Status Stag Reveret he H View Guider Settings s Error Y Error Euer fox x ha yje Auto Move 7 of 13 27 08 05 07 01 PM dbs autoguider v4 http www mso anu edu au observing 2 3m DBS autoguider_manua
55. rn the spectrograph to the diagonal position and set the grating angles Very approximate grating angles are engraved on the setting dial Changing Dichroics The properties of the dichroics are described in the DBS capabilities section When accessing the beam splitter the spectrograph must be in the vertical position See rotator handset controls e At the spectrograph unscrew all five grey lock levers on the beam splitter door about two turns and rotate 27 08 05 07 45 PM DBS Setting Up Guide http www mso anu edu au observing 2 3m DBS dbs_setup html 2 of 2 all five black knobs by one quarter of a turn until the they are in the open position Using the black handle on the door gently swing it open Use care as the beam splitter is cantilevered from the door s inside face e Push the door gently against the cable boom until a latch fixed to the cable boom locks the door in the open position There are three handles protruding from the beam splitter unit To change the dichroic locate the dichroic handle and release the four thumb screws securing the dichroic cell grip the dichroic handle and gently slide the dichroic cell out of the beam splitter unit Take careful note of the dichroic cell s orientation so you know which way round to insert the replacement Do not touch the dichroic or bump or shake the cell as the glass is only lightly constrained The four thumb screws are captive in the cell e Immediately store the cell in t
56. rolcs Long slit spectral resolution Spatial resolution Filters Neutral Density System throughput not yet available Slit masks Multi object observing 1 of 3 27 08 05 06 52 PM ANU Research School of Astronomy and Astrophysics RSAA http www mso anu edu au observing 2 3m DBS F 1 5 focal Reducer Observing Getting going quickly A brief overview of the required observing procedures Instrument changes Starting up the telescope Observing procedures Taking exposures The CCD controllers DBS Hardware control Starting the DBS control computer The decker Setting the slit width Changing filters Selecting arc lamps Autoquider Taking calibration data Bias frames Arc lamps for wavelength calibration Taking flat fields Telescope control for DBS observers Dome lights Telescope pointing calibration Rotator selection and control Rotator handset control The telescope CONFIGURE command The telescope SWITCH command End of night procedures Setup Configuring the DBS ready for observing Changing Gratings Changing Dichroics Setting the Central Wavelength Collimator Focus filter Filling the dewars Observing reports Trouble shooting Fault reports Copying your data to tape Data reduction Online resources Local and links Site information SSO weather Spectrophotometric standard stars Stars for correcting atmospheric absorption extinction data Not yet implemented slit transmission Diego Not yet i
57. t hand end of the main console Normally the control software will already be running If the DOS prompt is showing run dbs from the dbs directory 1 e cd dbs dbs Then select control gt status from pull down menus The mouse driven menus should be largely self explanatory but some details are given below The decker To move the decker click on Decker in the window labelled M2 to open the control dialogue box It cannot be set to specific positions but rather is manually driven into using button labelled gt gt and out 27 08 05 07 10 PM DBS Observers Guide http www mso anu edu au observing 2 3m DBS dbs_observing html 3 of 5 from using lt lt the slit With the dome lights or one of the arc lamps the Quartz lamps are too bright on the decker is clearly visible in the auto guider camera Use this to approximately position the decker or to see when you have driven the decker clear of the slit without having to take an exposure Setting the slit width To change slit width click on Slit located above Decker in the M2 window to open the control dialogue box Either specify the required value measured in arc seconds in the dialogue box and click Apply or drive the slit manually using the buttons labelled gt gt and lt lt You can check the slit visually on the autoguider camera using scattered light in the dome with the arc mirror out The orientation is reversed e g North up East to ri
58. t modified Wed Aug 10 2005 by Marilena Salvo salvo mso 27 08 05 07 10 PM 23mtelcon GIF GIF Image 921x582 pixels http msowww anu edu au observing 2 3m Imager 25mtelcon GIF Hs Console On Button Get VVarning Lights i amp Telescope Display a il P 1 m ma t 1 1 a 1 in a 4 i m il m 4 r J a P a re E 5 M 1 LL amp T ra a Ea 4 5 x 7l i i T un L i r T E m 4 m j s 1 a i r L i R h b Telescope Computer 1 of 1 27 08 05 07 12 PM 25mopen gif GIF Image 843x551 pixels http www mso anu edu au observing 2 3m DBS 23mopen gif r b 5 n PLI ILLIS l Building Shutter 1 of 1 27 08 05 07 36 PM DBS Trouble Shooting Guide http www mso anu edu au observing 2 3m DBS dbs_trouble html serv Trouble Shooting Fault Reports If none of the following helps please look at the archive of resolved fault reports and if you cannot find what you need there fill in a new fault report Other sources of help Before calling for technical support at night trying running the commands raurrs on the TCS console 1 e MATA to get a log of known outstanding problems Telescope problems SERVO FAULT or BUILDING DRIVE FAULT lamps at startup Running DIAGNOSE Primary mirror support pressure Focus control
59. tching between Imager and DBS blue involves switching two cables at the back of mallorn This is a temporary arrangement and the Observer needs to check with Technical Staff before their run to make sure that everything is set up correctly mallorn has also been known for hanging during the night causing loss of exposures Please make sure that the file cshrc in your home area contains the lines unset autologout limit coredumpsize Ok to avoid this and other problems Several users have reported there being no way to reliably abort an exposure mid way through without losing the whole frame Things have improved now but unless you are aborting a particularly long exposure or sequence you may want to consider waiting for the end of the exposure instead of risking to end up with more time consuming software problems The 2 3m does not have any data archive It 1s the Observer s responsibility to back up their data before they leave Failure to do so is likely to cause total loss of data as data disks are usually cleared by the next Observer at the beginning of their run Information about how to backup observing data can be found here Last modified Wed August 10 2005 by Marilena Salvo salvo mso 27 08 05 06 53 PM DBS Overview http www mso anu edu au observing 2 3m DBS dbs_overview html 1 of 1 DBS Overview The Dual Beam Spectrograph is a general purpose optical spectrograph permanently mounted at the Nasmyth
60. ticular park positions before removing or changing the grating dichroic etc If the telescope control software 1s already running this may be done using the RoTATOR command More commonly you will use the rotator handset located in the dome next to the DBS Changing Gratings When removing gratings the spectrograph must be in the horizontal position See rotator handset controls A suite of nine interchangeable gratings plus two mirrors in grating cells is stored in a cabinet on the accessories trolley Hatches to access the currently installed gratings are found on the ends of the DBS 1 e facing the front and back of the dome building To access the grating the grating angle setting must first be moved to Change grating The grating angle control dials are located on top of and beneath the DBS and can be awkward to reach If so use the control handset to rotate the spectrograph into a diagonal position Release the locking nut and rotate the large setting wheel to Change grating Re secure the locking nut Return the DBS to the horizontal park position e Gratings are removed by first firmly attaching a protective cover which also incorporates a carrying handle Take an unused grating cover from the storage cabinet located on the accessories trolley and blow it free of dust with the air gun that hangs on the near end of the accessories trolley e Open the grating access door Two thumb screws hold the grating hatches in place a
61. tp www mso anu edu au observing 2 3m DBS dbs_observing html 2 of 5 See MSSSO Telescopes Command Reference Manual a hardcopy of which is stored in the console room e Open communications with DBS autoguider hardware by typing TELS ENLIST TXA6 e Lights within the building are controlled by two lighting switches at the top centre of the console Set to FLUOROS OFF and INCAND OFF or INCAND PRESET Open the building shutter Press BUILDING SHUTTER OPEN on the console To start the building ventilation fans press VENTILATION FANS ON on the console e Open the mirror cover M RROR COVER OPEN on the console e Calibrate telescope pointing e Focus the telescope by using the autoguider camera as a TV display while driving the focus controls manually See the autoguider manual sections 5 amp 6 for details Taking exposures The CCD controllers VERY IMPORTANT There have been big changes to the CCD controllers See this page before reading any further The DBS cameras are currently run by Astromed controllers connected to a pair of workstations running UNIX located on the left of the Telescope Control System The second one on the left of the TCS is called mouldy From there the Red arm of the DBS is controlled The DBS Blue is run from mallorn which also runs the Imager This is a temporary arrangement and you may need to see the staff to make sure the computer is running the correct instrument or to learn how to swap between DB
62. tton bar near the top of the MaxIm window Working from the left press the 6 7 g buttons if they are not already pressed This will open the Histogram Information and MaxIm CCD windows The MaxIm CCD window contains seven tabs that control various camera functions Press the 70 tab the Setup tab and check that the CCD temperature is near 38C and that the CCD and Guider windows are both set to Apogee 2 Taking an exposure l Maxim CCD Tx 1 Settings Sequence Focus Inspect Guide Setup Type Minutes Seconds Delay s Cio a h p zi LES Bias NI X n atk Filters jf Stap C Fiat Camera Idle Guider linked to main 0 000 of 4 000 sec camera Temperature increasing buffer Temp Set 38 0 C New The 15 tab in the MaxIm CCD window is the expose tab Press this tab set the exposure type to normal and the exposure time to between 0 3 and 1 sec then press expose An image will appear in the CCD Image window in 3 to 9 seconds depending on sub fame settings Arrange this image window on the left half of the MaxIm display area This will leave the right half of the display area for the separate image display that opens when using the guide tab If you are setting up in the daytime and there is not enough light to produce an acceptable image of the slit go to the DBS status and control computer select any arc insert the arc mirror and take another image If the image fills the d
63. uence failed TELESCOPE SYSTEM UNUSABLE Telescope systems functioning and ready for observing Telescope systems abnormal but observing may be possible Primary mirror support pressure The primary mirror support pressure sensor sometimes gives inaccurate readings If the TCS gives a warning message about the primary mirror support pressure it is probably OK Best to mention it to technical support 1 of 3 27 08 05 07 37 PM DBS Trouble Shooting Guide http Www mso anu edu au observing 2 3m DB dbs_trouble html serv 2 of 3 anyway Focus control At times the focus control buttons at the console fail to move the focusser This problem appears to be located within the Auxiliary Systems Cubicle but the exact cause has not yet been identified Until it can be fixed control of focus 1s best restored by turning Telescope Systems off waiting a few seconds and turning them on again It is not necessary to shutdown the control software so you will not lose aperture calibrations etc Tertiary mirror The tertiary mirror may on occasion drive to the wrong position when a particular Nasmyth focus is selected More commonly it will correctly stow itself 1f the primary mirror covers are closed during the night but refuse to return to the correct location when they are re opened Should this happen issue a new TEL CONFIGURE FOCAL STATION NASMYTH A command or close and re open the mirror covers using the command instead of
64. uider SS wEmor Emar Guide star n c 159 zi M 82 B r sio Mavel To periodically check that the object is still in the slit stop the tracking press the expose tab and take an image this image will appear in the left image window It is normal to use a longer exposure time for this image than for the guide exposure Zoom on the object in the slit If the object is out of the slit use the cursor and information window to estimate the Y error Now return to the guide tab and jog the guide star Y position up or down by the necessary number of pixels You can use the small up down buttons to do this or type directly into the Y window Now press start and the autoguiding cycles will continue The guider tracking box will continue to be displayed in the right image window For long exposures check that he object is still in the slit every 10 minutes Or SO NOTE For successful in slit and offset autoguiding the telescope instrument rotator MUST be configured with the aperture at the rotator centre If the aperture centre is not at the rotator centre the field will rotate about the offset guide star and move the object out of the slit See pages 8 5 and 8 6 of the 2 3m Telescope Observers Manual 11 New Guiding aperture plates This feature relies on back scattered light from the telescope side of the aperture plate and is only useful in dark time scattered moonlight swamps the star images and makes guiding aperture plates impossible
65. use until a hand appears then drag the zoomed image around in the display window 3 Setting up a sub frame E m CCD 1 Settings Sequence Focus Inspect Guide Setup 1 Subframe x ffset Y Offset Width Height XS Binning Binning Auto E ibizim m m 12 Simple Auto dark mi Audible Alert e Full Calibration The AP47p CCD in the guider camera has 1024x1024 pixels The guider uses only one third of the CCD to cover about half of the DBS slit at a scale of 4 pixels arc sec Setting a sub frame to the boundaries of the slit will reduce the read time from 9sec to about 3sec If you take a full frame image with the expose tab then press the settings tab and drag a box in this image the subframe co ordinates will appear under the subframe windows You can type co ordinates directly into X Y W H windows The example shown here contains suitable co ordinates for viewing the slit and you can set these up by typing them in the appropriate boxes instead of using click and drag 4 Saving images to WinNT and UNIX Viewing finding charts on screen Maxlm allows you to save images of star fields in fits format from the slit onto both the Windows XP only and UNIX platforms and to read from and save images to your data account on the SUN UNIX system on data moist1 cicada _user_ This is done via samba The samba share WnurkyMata moist will map directly to your directory on data moistl cicada If you inten
66. w dispersions QI2 lamp is slightly fainter than QIT The blue arm will reguire longer exposures Dome Flats A ring of small lamps is installed on the telescope top end ring and may be used to illuminate the dome ceiling The lamps are controlled from the telescope console with the commands TEL SWITCH FLAT ON and TEL SWITCH FLAT OFF The following suggested procedure reguires you to first start the telescope control computers and log on The fluorescent strip lights in the dome must be switched off The incandescent lights are less important Move the telescope to zenith park and then slew it down slightly in altitude to prevent any harsh specular reflection off the ceiling For example TELS PARK TELS SLEW 75 Flats are best taken against the wind screens rather than the actual dome roof so issue the command TELS CONFIGURE WINDSCREEN CONTROL CLOSED Open the mirror covers once the wind screens have stopped moving The lamps brightness 1s controlled by a black round dial marked Flat field illumination control on the telescope console It is located under the other light controls near the top centre of the console With the lamp brightness set at around three quarters expect exposures of between 10 and 100 seconds depending on dispersion The blue arm typically requires about five times the exposure of the red Twilight flats The illumination pattern across the slit is normally different for flat fields than data frames ta
67. w mso anu edu au observing 2 3m DBS autoguider_manual db li E HE 0 elcome to the Double Beam Spectrograph and Imager Autoguider System These autoguider systems consists of two Apogee AP47p direct CCD Cameras that view part of the DBS amp Imager slits via Focal Reducer Optics each interfacing to a PC computer running MaxIm CCD Camera Control and Image Processing Software To lead users gently into using this guider this manual is arranged as a series of short sections beginning with the simplest functions and leading on to the complex On the whole the operational aspects of the DBS and Imager autoguiders are virtually identical hence only DBS auto guiding is mentioned in this manual Any operational or setup differences between the Imager and DBS will however be highlighted Contents Checking the camera Taking an exposure Setting up a sub frame Saving images to WinNT and UNIX Viewing finding charts on screen Setting a focus frame Using the camera as a television Inspecting telescope focus Setting up for autoguiding Connecting to the VAX The Move command Pulling a star into the slit In slit autoguiding Offset autoguiding Jogging the tracking box New Guiding aperture plates 12 Freezing the shutter 13 Daytime testing 14 Image processing Combining images to make colour images 15 In case of Software PC or power failure 16 AP47P Trigger Function SCOMIAM EW

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