TTL Anonymous

To misquote George Bernard Shaw:

"The digital underwater photographer is like the cod, which lays a million eggs in order that one may be hatched."

What is most important is to think before shooting. Some people think fast, some prefer a more considered approach. Some subjects require shooting lots of frames, others just one or two. People prefer different approaches and I don't believe there is a right or wrong approach.

Personally I shoot just over 1 shot a minute of dive time. So a 60 minute tends to yield 60-80 images a 90 minute dive, closer to 100. For me the number of shots is not the most important factor of digital. Instant image review is much more important, IMO.

Alex

100% Ack. Instant feedback and instant histogram are nice features.

Satura:

What i mean when i say multiple shots is:

1. I bracket exposure, personally i don't trust the screen or the histogram so mess with my fstops always

2. Much more important, and something i drill into my students time after time after time: bracket the composition! i am not a pistelero who goes bang bang bang. Personally i will take shots of a cooperative subject from 5 or 10 different angles, take a shot, move a little, try a different angle, Different depth of fields etc

Macro especially, get the whole animal, get the head, get the eye etc etc

Have a look at my website and see what i mean, lots of limited DOF and different angle of certain creatures

On film you were stuck with 36 shots, most beginners would take 36 photos of 36 subjects They only had 36 photos so wanted to get as many critters per dive as possible, couldn't see the results and usually ended up with 36 pretty lousy to average photos. Once they started bracketing exposures and composition then they would get 5 or 6 great shots per roll but usually only from 5 or 6 subjects per dive. But better to have 5 or 6 great shots than 36 bad shots. Once your experience goes up then your averages improve. This is why you improved so rapidly in digital, instant feedback. It is the best for teaching newer photographers to shoot underwater. I love it and it is a great tool. But for people who take photos for a living (Fred, Tim Rock, ALex, myself) the biggest advantage ( i think) is number of photos, not instant feedback, although that is a great feature and is a close second i will admit.

Now then on film, i would take 4 or 5 of each subject, sometime up to 15 or even a whole roll with a cool subject. Move the strobes, change f stops, change angles etc etc etc

However, pretty easy to run out of a roll of film that way. So, what happens then? Dive over

Digital gives a huge advantage in that regard, almost endless capacity.

Why not take advantage? Do i do it with every subject? NO, sometimes you can't and sometimes you know you have nailed it.

Believe me, people like Doubiliet, PErrine, Watt, and Rock (who you says need to go video) and every other successful professional underwater photographer works their subject to the extent that subject remains cooperative or every angle has been covered. Doubiliet routinely stays in the water for hours with people bringing him cameras and tanks to keep him going until he has had enough

If you want to get better results you have to show patience and perseverence and a lot of thinking. Be creative, think about your shots, don't just be a snap shot shooter. And to do this it requires multiple images of a subject.

And then there are those times when its just fun to shoot shoot shoot, like a shark feed or when the mantas are looping over your head for an hour.

Trust me, you are extremely happy to have a 1 or 2 gig card when you have 3 or 4 mantas circling over your head for 60 or 70 minutes, 36 shots just doesn't cut it in that situation any more. As i said, the biggest advantage of digital for me.

Perhaps i should have also stated that it is the biggest advantage for experienced UW photographers used to using film. Perhaps that would have explained my suggestion to the original poster as he is an experienced film person, (as am i) the histogram is a nice tool but after using film for so long the number of shots available is the biggest advantage because experienced professional film people (like the poster, Fred i believe was his name) have the tendency to get the exposure almost bang on anyway or just naturally bracket the exposures (like he was explaining he does, and how i have explained i do)

Anyhoo, i get the feeling i am rambling now

Later

Mike

One of the first bits of advice new photographers have always been given is too shoot, shoot, shoot. Film is always the cheapest part of underwater photography. And now we even don't have to pay for that.

Hi guys,

I finally tried my new rig in Key Largo today, the water was crappy, and there was a lot of surge, but I managed to get some good photos. I will post a complete report of my switch to digital later. For now, I just wanted to post on this topic to say that I will never shoot TTL again. If you go back to the first page you will see that I was affraid of TTL because of fish action shots, well, let me tell you, I took 80 photos today, and none of them is wrongly exposed, it is amazingly easy to shoot in manual with a dSLR.

Here is a shot that I took in my very first dive with the digital gear. Set to manual with D2x and Ikelite strobes in 1/2 and 1/4 power. I used a 60mm lens set to 1/100 and f11. There is some backscatter visible, the water was terribly bad, but I think it is well exposed.

>>There is some backscatter visible, the water was terribly bad, but I think it is well exposed. <<

Wow, Luiz I am always amazed when people tell me about bad visibillty and then show me a picture like yours , I definitely have to come out of the mud holes i have around here, you think I can ask for Climatic refugee status in Panama?

Nice shot,

Cheers

I think Fred is onto something with his flash compensation. What he's talking about is FILL FLASH, something that topside photographers refer to all the time (and we do a lot of the time but don't call it that). Topside, just about everyone uses TTL and they all use the Flash +/- to provide the correct amount of flash fill.

There are actual calculations to do this, which Fred has shown, but as a general rule, Galen Rowell and Thom say "Use -1.7" and it works. Except for shiny subjects of course.

Well, how do you "Use -1.7" underwater when you are using manual flash? You have to do the calcs, or else shoot, review, shoot again. For those once in a lifetime shots where you only get to shoot once, the calcs sure are handy, thanks Fred!!!!

The Fuji S2 that he's using helps a lot. The Aquatica housing has a stay-depressed control that you can put on the Flash +/- control. The camera lets you take photos while that button is depressed, so it's really easy to bracket the flash exposure. You just shoot, spin the knob, and shoot again, then spin it the other way and shoot again...

Cheers

James

Not convinced about calibrated TTL - as you are calibrating a moving target.

I accept it works most of the time. But say you take a shot and TTL gets it wrong. So you compensate the TTL - and recompose and shoot. This time your frame is slightly different and TTL gets it right - but your compensation means its wrong.

TTL calibration is fine when you are basing compensations on your experience when shooting on film.

But digital is different. When you can see the results and are changing the compensation based on what it actually did (as evident in the LCD/histogram) then you are better off compensating a manual setting that will always give the same power. Rather than chasing around a potentially changing automatic setting.

Alex

I am very impressed with the lattitude that the D2x shows in the highlights. It seems like I get good exposures with no (or minimal) blown highlights when within 1/2 - 1 stops of optimal exposure. These are shots that would've blown out with my D100. It makes it much easier to shoot manual with this camera than with the D100.

This improvement seems to be a combination of sensor enhancement and firmware (incl JPEG engine). Very impressive - a big concern of moving back to digital was giving up the perfect TTL of my F100.

I started with digital UW two months ago with an Aquatica housing, my concerns was the same that almost people here, the TTL, but I never used TTL for wide angle, just for macro. For some time I tried to wait for the Aquatica TTL circuit, but after saw a lot of good results here, finally I done and got a housing.

My first dive trip with digital was in Cayman two months ago and now I'm sure that I don't need TTL any more, the first time I got dificult to adjust the LCD light and compare it results with histogram, but after the second dive it was ready.

My big problem was that I had to learn again to look at the scene and to adjust the aperture, exposition and the flash power, but after one week of tests, everything become like drive a car, the brain make automatic this task.

Regards

Hello WetPixelites,

I have looked at the responses to my pro-TTL discussion the other day and it is clear that at least some people are not fully understanding the technique and its applicability. So I’ll try again. Mike Veitch in particular makes the statement that dialing in several different levels of compensation is the “slow route†compared with just changing the aperture setting as the guide number dictates you must do as the flash to subject distance changes.

In the case of a flash-only exposed picture, Mike is correct that changing the aperture alone is all that needs to be done to get the right exposure using manual guide number exposure. This assumes that you are able to accurately guestimate the distance between subject and flash. And that you know in your head the changes that must be made to the aperture for each distance so that you don’t have to keep looking at a written table to know which aperture you need. If you have to take your eye from the viewfinder to re-estimate the distance this takes time. If you have to look at a table this eats up time. If you have to move your eye from the subject to the aperture readout in the viewfinder, ever this takes a little time. And in all three cases you have lost “sight†of your subject in the viewfinder and you have to re-establish your framing and composition after you make the aperture change.

Using TTL for flash-only pictures you set one setting, based on the subject rendition you want, on the compensation control (based on experience), and this doesn’t change if the distance between flash and subject changes, nor is it likely to change much if your composition or framing changes 10~20% with different angles. If you want to bracket the shot so you have several exposures to choose from you can do so in several ways. The first is that you can reset the compensation control to another amount. With some housings this can take time. A second alternative is to use the auto-bracket function many cameras have today. If you shoot your flash-only shots in manual exposure mode you make a setting like 1/125 and F22. And in this case the auto-bracket on most cameras will affect neither the aperture nor the shutter speed. But it will change the output of a TTL strobe. Thus you can make two consecutive shots at two different flash outputs, which you predetermine, as fast as your strobe recycles. In very many when I anticipate a lot of macro shooting I preset the bracketing for a .3 f-stop variation such as 0.0 and –0.3. And then set the initial compensation to the exposure I think is most likely to be correct. And then am able to keep my eye on the subject (for focus and composition) in the viewfinder the whole time I am shooting that subject unless I get the underexposure warning signal in which case I have to open the aperture a bit.

With a fill flash situation, the mechanics favor TTL far more.

In the case of Mike’s guide number based manual exposure, he still has to change the aperture to keep the exposure the same (correct) as the flash-to-subject distance changes. But additionally, if he wants to keep the water color or background, whose exposure is primarily determined by ambient light, the same in each shot, he must also change the shutter speed appropriately. For example if his meter tells him the blue water color and reef background he wants requires 1/125 at F5.6 (and f5.6 is also the aperture he needs at his initial flash-to-subject distance), then if the subject moves closer enough to require an aperture change to f8 to avoid frying, the when he changes the aperture to f8 he will also have to change the shutter speed to 1/60. This requires two camera control changes, which takes even more time, and more loss of contact with the subject. And it also introduces the potential of more subject blur due to motion at the slower shutter speed. Alternatively Mike could change his manual flash output to half of the original flash, which has the advantage of at least keeping the ambient light exposure component of the shot the same. But has the advantage of his having to turn the camera-flash combo into a position where he can read and reset the manual output of the flash. This takes even more time ( and more loss of subject concentration in the viewfinder) and requires making additional movements which can disturb the subject more.

The TTL alternative. With the compensation at 0.0 I take an ambient light reading and set that shutter speed and aperture combination. (Let’s assume it’s the same 1/125 at f5.6. Since I’m shooting ambient light plus fill I widen my flash brackets because the flash is providing only a part of the total light and its changes must be greater to make a significant difference in the total exposure. So I generally set the auto-brackets for a full stop difference or 0.0 and –1.0. I then set the normal compensation to about –1.7 or –2.0 and then move in on the subject to focus and frame it. At this point the camera exposure-wise is virtually on auto-pilot. The TTL compensates for moderate changes in distance, subject reflectivity, and even composition, so my eye stays on the subject in the viewfinder for one pair of shots after another until I’m finished or the basic parameters of the picture change significantly. It also makes and effort to compensate if a big shiny fish turns at just the wrong angle and becomes a mirror or a shark turns its white belly towards you.

This method works extremely well with most post-F4 Nikons (F90x, F100, F5 (and probably F6) And if you modify your compensation control so that it can be “locked†to on position, you can make all of the compensation changes by simply rolling your thumb along the main input control dial which is usually on the back of the housing. This replaces the frame count with the exact amount of compensation set, and you can still fire the camera with this button “locked†to display the compensation, which is something I don’t believe you can do with Canon. What you cannot do with the compensation button depressed is change the aperture or shutter speed. And this is why it needs to be easy to lock and unlock this control. I first started using this technique with an F90x in a Nexus housing. I remade (with a machine shop guy’s help) the arm of the compensation control so that I could change it on or off with my hand on the handgrip. And added a large thin plexiglass knurled wheel onto the housings main input control dial so it also could be changed with my hand still on the housing handgrip.

When I ordered my three F5 housings from Seacam, the main input control was already very reachable from the handgrips and I simply asked Harald to put a much longer lever on the compensation control and remove the spring that “recenters†it. Harald did a great job on it and I can turn on and “lock†the compensation control with a flick of my left forefinger, and turn it off for frame count.

This is why I feel underwater TTL strobes endow my film cameras with capabilities I am unwilling to give up to get digital imaging. And why I will wait for a good I-TTL from someone like Hartenberger in Germany to go totally digital. However I do feel there are situations where digital capture will provide me with advantages. These include shooting large marine mammals with ambient light only and many over/under shot situations where seeing the exact balance between the ambient light topside component and the underwater flash exposure would be very helpful.

Like Alex Mustard said in his paraphrased quote, “Digital Photographers are like cod, needing a million tries for one success.†The digital philosophy seems to be shoot, shoot, shoot and then keep the few good shots out of the thousands. And which still may require a lot of extra time on the computer in Photoshop to make them really right.

I prefer a philosophy of watch, learn (what the subject does and why), and then shoot carefully. I often do a dive without finishing the whole roll of 37 shots, even on dives up to two hours. Despite having had five underwater stories in National Geographic (manatees, giant octopus, giant cuttlefish, crinoids, and frogfish), all of which were done on my own initiative and at my own expense (an on an average of about 100 rolls of film or less each), I rarely shoot over 300 rolls of film a year.

In most cases I would much rather have a second housing with a different lens on the dive. And have (only) 37 more TTL shots, than have one digital housing with 200 or even 400 non-TTL shots. I use a sync cable system that utilizes a very nice five pin wet connector made by Impulse in San Diego which allows me to change a pair of strobes from one housing to another during a dive. I love being in the water to watch and learn about the animals and photography is simply my ticket to get there. I would much rather spend extra hours in the water than in front of a computer fixing pictures that it would be much better to shoot really right to start with. And TTL is a great tool for shooting right.

divegypsy

Yes. I can see that there are times where TTL may come in handy, although as one who has essentially never shot film underwater I can only guess. I've gotten fairly good at estimating exposure. I usually do it from the lens I'm using and subject size. I've shot with my current setup enough that on macro shots I'm seldom off by much even on the first shot.

I think you under estimate the advantages of a DSLR. The dynamic rage is good enough that you'd have a hard time telling if a shot is a stop under exposed after adjustment. You don't have to be perfect. Just be close and don't clip the highlights. At the risk of losing all respect from film shooters, here's a quick demo. Three shots with the same lighting at F/11 , F/16 and F/22 compensated in raw conversion. No other adjustments.

The F/16 shot was perfectly "exposed to the right" according to the camera histogram. Can you tell which one is under exposed and which is over?

Here are 100% crops in the same order to help with your selection.

Look at the EXIF data of the photos for the answer.

It's more difficult when there's natural light involve, but even there it's usually possible to compensate a wide range of exposure with the added help of curves.

Hi Fred,

I have seen (and admired) your images many times over the years. You have a sytem that works (obviously) and if it ain't broke then don't fix it. I would never tell you to change the way you shoot - but I do think that you should not discount the ease, effectiveness and productivity of shooting manual on digital. And regarding it as a hindrance to you shooting digital seriously. I for one, would like to see what you produced with a digital camera.

On film TTL is essential IMO. On digital it is not. This is because we have instant feedback from the LCD to tell us if our exposure is wrong. But just as important - as soon as you start shooting manual flash (with the instant feedback) - you realise that the settings hardly change at all. And your exposure is rarely wrong. Most of the time we shoot subjects from very similar distances and as a result the settings are the same again and again. I think film photographers think that we are endlessly fiddling with strobe powers and apertures to get correct exposures - but actually the settings stay remarkably consistent.

Also when you are shooting this way you quickly learn to adjust settings when required - opening up aperture or increasing flash power if your subject is significantly further away or a bit darker. Its pretty much subconscious. In the same way that you might adjust your TTL compensation - for a different subject or shooting setup.

The reason I started this thread is because it is very hard to communicate the lack of need of TTL to an experienced film shooter. When I was a film shooter, I knew how many shots I had got with TTL and would not accept others telling me that it was not necessary on digital. I thought that these new digital shooters, who know lots about computers and not much about UW photography, could not be right. But they were. The aim of this thread is to provide a weight of evidence that manual flash really works and you don't miss shots.

I would never say that TTL is not essential for film. It is. But on digital I would honestly say that I rarely miss a shot underwater because of the wrong flash exposure. Like you I do a lot of UW wildlife photography - I take on subject matter - such as spawning fish that are fast moving and aren't going to repeat the show. And if I thought that manual was loosing me shots then I would shoot with TTL, even if it meant shooting on film. But even when shooting subjects where capturing the moment is essential - I do not feel that manual is in any way a disadvantage.

Alex

Hello again Wet Pixelites,

The discussion continues. Having run numerous tests with my Fuji S2, which my girlfriend Pat now uses, I can easily say that many "near misses" can be improved considerably with careful use of the raw format and programs such as Photoshop. However, such corrected or rescued images, according to a person as knowledgeble as Bruce Fraser in Real World Camera Raw with Adobe Photoshop CS2, are usually of lower quality. And quoting Bruce, "Correct exposure is at least as important with digital capture as it is with film..." So a lot really depends on the final uses which you hope for with the picture. My final goal for many years has been quality magazine and book reproduction, which is one of the more critical uses of photography.

Last year I had a very long discussion with Heinz Ritter, the chief editor of Germany's Unterwasser Magazine. He also single-handedly produced Unterwasser's predecessor UWF, which in my opinion was the highest quality underwater magazine that I know of. For UWF Heinz personally did the scanning for many of the reproductions, and today he likes the Canon digital SLR's very much for his personal shooting. But when I asked him which he would prefer to work from in a magazine, he said his real preference was still a properly exposed transparency, because the final digital image used for printing can then be truely tailored for a particular printing press. Heinz said that many of the digital scans and digital images he receives from photographers have been so altered to "look good" on the computer screen that they can be reproduced in pirnt only with great difficulty. He went further to say that many of the scans he had received from a well-known digital-only underwater photo agency had proven to be unusable after conversion to CMYK, which is necessary for printing, and he had found it necessary to spend a week at the agency teaching them how to properly prepare scans and digital images so that they could be used without excessive extra manipulation.

I also had discussions with picture editors at National Geographic, German GEO, and National Wildlife. And while all said they were willing to consider digital images, every one of them still expressed a preference for film.

The point of all this is NOT to say that digital underwater photography is not worthwhile, or even that it is inferior to film. Only that once you start "saving" images that aren't "just right" to begin with, you may be introducing additional problems, depending on the final use. For personal consumer consumption, I believe digital photography is one of the best things that has happened in photography since I started shooting in the 1960's. It allows most people to shoot many more pictures at virtually no more cost except their own time. It gives them the chance to see any mistakes and correct them immediately rather than miss a shot that could be important to them. It is environmentally better because there are far fewer noxious or harmful chemicals used and released into the environment once the equipment is manufactured.

And I, personally, am looking forward to using digital (with my new D2X) for almost all of my topside photography (and some underwater photography) in the very near future because good TTL strobes, like Nikon's SB800 are available for topside use.

I am simply saying that I learned underwater photography the old fashioned way, with manual strobes and guide numbers. And then graduated to TTL which I feel is vastly superior in its consistency and ability to achieve a precise balance between ambient light and strobe fill. And I am unwilling to go back ten or twenty years on strobe control and technology, simply to get digital image capture, and the advantages that has. I will use each, film or digital, where I think each offers me the most advantages. And the best opportunity to succeed on those one-shot opportunities. And right now, underwater, that is with film and quality TTL strobes. Hand me some professional quality i-TTL underwater strobes equivalent to my Hartenberger 250's and 625's and I'd probably go totally digital in a minute.

divegypsy

As a wedding photographer topside, I am completely sold on TTL with my Nikon D70/SB800. There are one-time opportunities for shots that I can't make otherwise, and they make or break the shoot. Very often the same is true for me underwater photography. If I can rely on the camera to set the flash exposure, I can concentrate on composition -- and get a properly exposed shot 99% of the time. So, pardon the contrarian view, TTL flash is my preference.

However, water absorbs light strongly. You need additional strobe power for underwater use, beyond what the standard strobes like the SB800 will deliver. Unfortunately, the older UW strobes do not work with the newer digital cameras. The digital camera makers have each invented complicated new strobe control protocols that won't work with earlier strobe gear from Ikelite, Sea&Sea, and Nikonos. Some of those old strobes are great devices. I suspect one reason many photographers don't use TTL is simply because their old strobes won't support it, and they are comfortable and familiar with their old friends.

But there is an inexpensive converter made by a little German company that will translate those new camera stobe control protocols to generic strobe protocols, to allow SOME older strobes to work (must do pre-flash -- see list later). There has been no mention in this discussion of these aftermarket TTL converters (which work well with Nikon, Canon, Olympus digitals). I use one. With a compatible strobe, it works well.

For me, TTL flash is simply a useful technique, a tool. I can use it or override it and use manual settings at any time. For a photographer who seldom has an opportunity to shoot underwater, it is a great help, because the chances are most shots will be good, without a learning curve. For the pro, still consider it for the one-time photos that you otherwise might miss. Again, it is just a tool, to be used with your knowledge and experience.

Here is a pointer to the maker:

http://www.heinrichsweikamp.net/blitz/indexe.htm

Here is a list of supported strobes:

http://www.heinrichsweikamp.net/blitz/indexe.htm

Here is a pointer to supported cameras:

http://www.heinrichsweikamp.net/blitz/indexe.htm

So, I just spent some time looking for this great thread because I specifically wanted to ressurect it from the dead for some perspective. Warning, ZOMBIE thread!

On message #85 above I show my first fully manual (non-TTL) shot with my D2x 8 years ago. Back when this thread started I didn't even want to think about trying to photograph fish without TTL, needless to say, today that's all I do (and well I like to think). Now I am upgrading to a D800 and there are a myriad of options for TTL, the one I am looking at is the Ikelite TTL adapter. What are you guys doing these days? Shooting TTL or hanging on to greater control with non-TTL? How reliable and accurate are those adapters? Is there any advantage in getting one or should I just keep shooting the way I have done for the past 8 years?

There are times when i think that i want TTL that i can switch off... a bit like having ABS on my motorbike in certain conditions it provides security but most of the time it is off. However i have got used to my flash settings in relation to my camera settings and distance to subject, so i cannot see me switching to Fibre Optics or a TTL convertor. It is funny as on my sea and sea MMII i used TTL and now i have no real need for it. I like the control but i do think that when diving in a new environment you may mess up that chance encounter. But i think that f8, 1/125 and 1/2 power or thereabouts on the Strobes can give a good first setting as long as i am close enough....

Holy thread resurrection Luiz!

I am now on my third DSLR: D70, D90, D7000 but still have not gone TTL, mostly due to the fact I still use YS 120 strobes, I just picked up a New To Me one last year for $90! Nice

Hi Luiz,

I spent couple years shooting with 5dmk2 without any TTL because the old Mathias TTL converter that I had working with my 5d didn't work with 5dmk2. I really missed that feature for few months, mainly for fish behavior, but I we are capable to adapt and change our mind to shoot without that making the adjustments manually.

Since Feb this year I upgraded to 5dmk3 on Aquatica housing and started to use the YS TTL Converter/C with couple YS120. I am really glad to have it back. It is very reliable.

The only cons I have about that TTL converter is related with appertures over f/22 where we need to increase the light compensation using the dial in the converter, but it doesn't vary, I just got in mind the compensation for f/22, f/25 and f/32 and it became automatically for me.

Actually I've been quite comfortable shooting with manual for the past 4 years with my Subal ND700 (no TTL) . In fact i got better exposure results than the old days when I used TTL on film camera (F100).

Recently I'm considering upgrading my set-up from Subal D700 to D800. Just wondering should I keep using manual or should I switch to TTL with FO sync (talking about macro shots only, for WA I would definitely stick to manual) ?

I also heard (from another thread) that with TTL the shutter sync speed would be much limited - is this true or not?

Any comments & suggestions?