my paper on underwater photography technique.
Contents
1. R 3 000 4 000 6 600 8 990 B 1 200 1 425 1 500 And these are the sample numbers for shooting in Eilat Israel green coefficient 100 0 R 350 0 630 0 700 0 900 0 B 103 0 110 0 125 0 160 0 Tool wise I relied on my own raw processing flow www lazyconv com configured for multiple 8 Copyright c Oleg Kosyakovsky white balance preset directories for all the red blue combinations above As aresult I was able to find acceptable to good colors for all the images Illustration 7 Colors of the scorpion fish here match what others achieve with flash Problems and suggestions for improvement The need for more megapixels It s argued a lot but the more is the better Then since it is very difficult to frame underwater I had to crop a lot The 6 megapixel camera I used enabled to produce usable slides 10 Mp input file but having larger resolution would help to avoid upsizing The need for better color handling In my case I didn t even try to match colors individually on each shot but still burned too much time on this job I d recognize three areas for technical improvement 1 Diving technique The challenge for me was to freeze myself before taking the shot This includes both vertical floating balance and horizontal movement 2 Gear rearrangement E g I would like to have higher resolution but need to invest into things other than sensor too in order ti make use of it 9 Copyright c Oleg Kosyakovsky 3 Optim2. Using KonicaMinolta 5D DSLR underwater in Ewa Marine flexible housing Table of Contents NAAT CN a ote cates ere rss nearness ier ca eines ed cess wages E A E E cron ate 2 AM imponant note ON weight DA ANC Cis ccncerscdsatesdnccncussnccaeesenseatte sadenbesbndencuasnceaeesecdeatee irai ediki E ENEE 3 The CHOICES ol Cami hl TIO Cys coset ccsenetiassaeerepasaaaeraseeontaaccenetl ads anenaphiesaesaseeontdacsanahtaassnerepiiedaseaseeeetiaeds 3 Lens Se NC CU iee cesca useage te yas oate E E A E 4 Color corr cuon TINE oases ats nes e a dd saves pee E E E N er tentsons 4 Ce CUMIN OS a oe E EE E A E a a 5 Ar eME AE Eee E E E E A E A E A EE EAE 6 Pre a eE ea E E 7 COT 201 Or O a E E E E E E E E E 7 Problems and suggestions for WNPTOV CMGI xcawsnsesscananesandanseousmnnweaaeitanawouisendweanndaessenciunnedusimesieusnvensanaaae 9 Won toce ome kra ec Veg E eee ene E eee 10 l Copyright c Oleg Kosyakovsky Introduction This paper presents an economical way of taking underwater still photos of a reasonable quality Economical means the user already has land camera equipment while the additional cost of bringing it underwater is minimized The technique being described relies on autofocus digital SLR or large sensor bridge camera being used in underwater case without a flash Specifically I used Ewa Marine soft case www Ewa Marine de which is the most affordable solution while still enables to dive up to 20m The baseground technique I
3. ctive weight variations are dangerous for free diving I felt I got tired quite quickly when trying to snorkel free dive with this setup Given the effort required to reach the surface this doesn t sound attractive So Le Ve Ar Aai yA Te ws your scuba certificate and you are set af P TEF j yo Y 4 a Pt s a i O CER TGS ELGTAS 4 a i a P ty A Poy r ye ty i lt P 4 lt of A 4 g y 4 s a An i AAD E ht AL sll OO BM df Li 1 5 ae Sa Illustration 2 Scuba diving allows to stay beneath and wait for the right moment The choice of camera model The Ewa Marine UX P enables pressing buttons located on the back or top right of the camera Horizontal mode switch wheels are no go and vertical control wheels could only be turned while on the surface I have Sony A100 and KonicaMinolta 5D DSLR s The A100 has too much stuff being dependent on left side wheel this makes it undesirable for the purpose The ISO and Function 3 Copyright c Oleg Kosyakovsky buttons of the 5D come to the rescue the latter enabling to access settings of focus mode Still you cannot control shooting mode Av Tv P etc and white balance Front wheel controlling aperture shutter time and exposure compensation could be turned from time to time but it s quite a procedure you cannot perform it too frequently Additionally it s beneficial to have ISO 800 as an option this is where the 5D shines It
4. employed for achieving close to realistic colors underwater is highly discussed on Internet the particular person whose paper I read first is Alex Mustard The idea is to record as much useful color data as possible through cutting off excessive color cast s by a filter then postprocess to achieve the desired colors My paper adds several practical tips that will help to put this technique into work from the very beginning Large sensor read DSLR is essential because the postprocessing involves amplifying red and to a lesser extent blue color channels this will cause excessive noise unless the image to start from is of a high quality Still there is visible noise see Illustration 1 but it s not something I cannot live with Rete te oe a i y I p ss Eh Illustration 1 The smooth areas exhibit some noise because of color restoration 2 Copyright c Oleg Kosyakovsky An important note on weight balance The use of soft case results in the air volume and the floating balance being highly dependent on the depth The deeper you go the heavier you become And from my experience even if you leave only the minimal possible amount of air in the housing you need extra weights and some effort to submerge when on the surface But then at 2 3 meters depth the balance becomes negative and you need an effort to go up What I m trying to convey is that the proposed setup is better be used for scuba diving only The extreme effe
5. ization of postprocessing I can leave with the color results I managed to achieve but time spent should be reduced significantly Gear issues in more details a Vignetting from the lens port Sometimes on right side sometimes 1n the top right corner The reasons e the lens cannot be perfectly centered in the port should have invested more into determining absolutely the shortest lens adapter length sometimes the adapter assembly turns aside a bit causing extreme vignetting longer adapter rails or shorter lens together with older model baseplate that has guides for the rails would help b Reduce the amount of correction This would reduce the noise and improve overall quality Use stronger fluorescent filter faster lens may be required to avoid hurting AF operation too much c Keep the lens closer to the port window glass To reduce the impact of the glass on the picture Internal focusing lens is required to achieve this Want to see a larger size picture To answer the question whether this method can deliver quality results just turn the page 10 Copyright c Oleg Kosyakovsky c Oleg Kosyakovsky The end Author Oleg Kosyakovsky oleglk yahoo com 11 Copyright c Oleg Kosyakovsky
6. ollowed his advice That turned out to be right at the postprocessing green multiplier was always the smallest among the three 4 Copyright c Oleg Kosyakovsky Camera settings This and several following sections were originally written for my own use to guarantee following the correct procedure at the morning before each dive This explains their user manual style e Power save effectively off so that other settings aren t lost e Focus point illumination for as long as possible sometimes it s hard to see the viewfinder image and the illumination provides at least the minimal hint Immediate preview off you don t want the screen to flash after an exposure Shooting mode portrait program reasonably favors fast shutter while still closing the aperture 0 3 0 7 stops if possible Metering mode matrix worked fine for me Exposure compensation 0 7 determined experimentally for my camera sample ISO 400 there s not much light AntiShake on all the time Focus point selection central while not so good for composition forget about focus recompose it employs your most reliable sensor and then focus point illumination shows you where the center of the frame is The latter reason 1s essential the viewfinder isn t clearly visible in Ewa Marine cases e Release priority AF focus conformation indicator is hard to see so I had to press and hold the shutter release while relying on the camera to fir
7. ou cannot trust your eyes while examinating the images Instead either a reliable reference is needed or you make the picture look as you like it in the end of the day no diver can see the true colors 7 Copyright c Oleg Kosyakovsky To have a color reference I included gray air tanks of the buddy divers into the pictures from time to time see Illustration 6 Illustration 6 Leopard shark is the main subject diver serves for color correction Then an interactive RAW developer UFRAW in my case could be used to measure red green and blue coefficients required to make the tank neutral gray Same coefficients could be used for other pictures taken at the same time and place But of course you cannot have a reference for each and every shot My approach was to arrange a set of coefficient combinations and for each picture choose the one that suits better In order to do so I filled a table with coefficient reading available see above and chose 3 4 gradations of correction per each of the channels Despite having fluorescent magenta filter green channel had to be reduced in all pictures So I assumed green coefficient to be 1 0 while those for red and blue were larger than 1 0 I denoted the smallest red coefficient as R1 the next one as R2 and so on I ended up with all the combinations of R1 R4 and B1 B3 B4 Here are the sample numbers for shooting around Phi Phi Island Thailand green coefficient 1 0
8. s possible that Sony A200 A300 A350 cameras suit better need to check I first tried to shoot with HP945 bridge compact The thing could be mounted into the housing but there were 2 major problems e EVF is nearly impossible to see while I prefer to keep that backside LCD off to avoid heating e Zoom buttons are unintentionally pressed by the housing itself So I just left this idea and went for the SLR Lens selection I used KM 18 70 3 5 5 6 fixed at 18mm I wanted its close focus ability though I m not sure I was ever able to approach the subject as close Otherwise an internal focus lens is preferable since one could place it closer to the port glass Theoretically wider lens equivalent of up to 24mm should be better but you should be trained more than me to come even closer to your subjects If the theory comes out true Carl Zeiss 16 80 f 3 5 4 5 should be the ideal choice for Sony Minolta system Color correction filters Internet sources suggested having color correction filter to reduce the amount of numerical white balance correction Do a search for Alex Mustard and several topic related keywords I had access to R25 red FL D fluorescent magenta 81C orange or brown My red filter eats too much light to be usable Theoretically I should have been using FL D in mostly green waters and 81C in mostly blue waters A local diving club manager and UW photo enthusiast advised me to stick with magenta filter I just f
9. st focus then fire e White balance auto just to have anything e Output RAW or RAW JPEG I sticked with the latter though the JPEG s had no use 5 Copyright c Oleg Kosyakovsky Assembly details e Arrange a weight of 300 350 gr of the size and shape that could be placed in the housing below the camera Wrap it well to ensure it has no sharp edges I used 4 large fishing lead weights stuck together by a gluing band e Pre assemble your AV110 adapter and remember what length do you allow when attaching it to the camera At its longest physical length the lens should protrude a bit beyond the adapter yes I mean it e Load the camera with fully charged original battery and memory card large enough so that you don t have to open the housing on the site 4GB card enabled 324 RAW JPEG shots on the 5D enough for 2 dives I had on a daily trip e Partly wrap a sack of silica gel into some cellophane or so for protection and attach it below the lens with a rubber ring to non rotating part of the lens e Attach the adapter see the paragraph above regarding the length and protrusion e Stick an eraser or anything alike between the lens and adapter rail so that zoom ring 1s locked at the widest setting e Insert the camera and the weight into the housing e Wipe thoroughly the opening of the housing and close it e Ensure the lens is centered in the port Recheck this frequently during the dive Illustration 3 shows the camera
10. with lens adapter attached Illustration 4 shows the whole setup Illustration 3 Lens adapter attached Illustration 4 Camera installed in the aeie misses case ready to go note the wrap with weights at the bottom 6 Copyright c Oleg Kosyakovsky Pre dive settings checklist The portrait program mode of the 5D has its default settings which is OK The problem is that these settings are restored each time the camera is switched on or returns from power save To minimize the impact delay power save so that 1t won t occur during one dive Before descending e Switch the camera on Verify that portrait mode is chosen Set ISO value to 400 Set AF point selection to center spot Dial exposure compensation of 0 7 Inflate the case depending on how deep you are going to dive And use the opportunity to take a couple of pictures right from the water surface like TODO ref below the unusual viewpoint could be rewarding Illustration 5 Raindrops as seen from the sea surface Color restoration Disclaimer I m describing my way of doing this but with no claim that it s even close to optimal Moreover I consider amount of time spent on this being unacceptable So the aim is to obtain realistic underwater colors as if you are diving with a torch e g bring normal light source underwater At depths more than a couple of meters these colors are more vivid than what you normally see during the dive so y
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