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For those wanting to get the most out of TTL flash, I'd advocate learning about subject reflectivity/tonality and its effect on correct exposure with any auto exposure system. That way you can evaluate your subject first, decide for yourself if the system is going to do the job. If it's not, and is going to under or over expose, then dial in compensation before you take the picture. Personally I hate reshooting; anything that wastes time when time is so precious, or makes me miss the moment, sucks.

 

If you want pictures where the subject and the moment are king, choose the system that gives you the least number of controls to fiddle with in order to get the exposure of YOUR choice.

 

For some that will be TTL, others it might be manual, and sometimes circumstances will dictate.

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when taking underwater photographs? As I said before, TTL flash exposure is merely another auto exposure mode and removes control away from the photographer.

 

Exactly, no argument from me or anyone else. Like any automated tool, if it doesn't give you the results you want, don't use it.

 

As Mr. Haas pointed out, many well known pros used TTL for wide angle beginning with the Nik IV. They would dial in negative exposure comp. I was taught this technique by a well known pro. I found I didn't like the approach, as the amount of EV comp needed to be varied by some cryptic formula.

 

Unless you are using guide numbers to calculate the proper amount of flash for your given exposure settings, then you are just guessing. The creative part comes on the second shot. Sometimes there just isn't a second shot.

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It is fantastic to see such a lively discussion with such different views.

 

One of the reasons I brought this topic up (apart from the ones mentioned at the top) is that I am taking an Ikelite D80 TTL housing and strobe to Cayman at the weekend. It is my intention to write an article revisiting TTL on digital.

 

For me one of the biggest limitations of shooting TTL underwater is when using two strobes. If you are using TTL then in nearly all cases both strobes have to give the same power output. While this may be fine much of the time, there are also many occassions where it will not be ideal.

 

Alex

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Good point Alex... This may be one of those occations where TTL limits your creativity.

 

With the ike housing the easy alternative is to swich to manual for those particular shots...

 

But with the "inhousing" heinrich weikamp converter I dont think that this is possible...

 

But I guess it is possible to carry an extra set of diffusers... but that means even more gear to carry with you.

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Alex,

 

Good to hear you will be actually trying iTTL underwater :wacko:

 

As far as dual strobes and the same power ouput from each....There are many, many methods for "cheating" strobes on TTL to achieve ratioed lighting. Here's a few I've used.....

 

1) Pull the one strobe back further.

 

2) Have mutiple diffusers rigged up you can slap on with bungie cords to decrease light output

 

3) Aim the strobe you want to emit less light away from your subject using "rim" lighting.

 

Even an iTTL strobe can't put out more tha a full power dump....You just have to figure ways to keep the light away from your intended subject / lighted area.....

 

You will love the Nikon D80. Carlos Villoch shooting many articles for Sport Diver articles was picking up a couple Nikon D80 bodies and his new Ikelite housing and dual DS125 strobes last month. I'm looking forward to seeing his work created with these fantastic tools ;)

 

Looking forward to seeing your TTL article!

 

dhaas

 

post-244-1165411909_thumb.jpg

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Great Alex,

 

I can't wait for my next issue of Underwater Photography! Personally I think you will never go back.

 

For ratio-ed lighting there are several more ways to do it. The suggestions that David made are probably the easiest. But with the Ike housing and iTTL you can switch the primary strobe to TTL and the secondary to manual (on the strobe) and select the power level (one of 4 levels onto 1 of ten however). This can give you ratioed lighting. Its not written in the manual but it works.

 

Expanding on David's technique, I have one of my strobe arms rigged with one of Ikelite's release handles. This makes it quick and easy to handhold the strobe for even more ratioed lighting positions.

 

To make uw TTL a truly mature technology it would be convenient to have FEC on each individual strobe. Subtronic is the one to do it, as they have all the TTL circuitry built in to the strobe.

 

Remember there is no possible way to make ratioed lighting automatic. There are too many variables and the photographer will always want to change them. Think about how this is done with iTTL land strobes--by adjusting FEC for each flash separately on the commander. But its still TTL because although the ratio is decided by you the system still outputs the required light for perfect exposure. Its the same underwater. For a given setup by either adjusting strobe angle or power you will get correct exposure in the ratio of lighting you prescribe.

 

The main point is that with S&S, Ikelite and Subtronic TTL you don't have to decide between manual and TTL. You can use it sometimes or all of the time to get what you want. All SLR cameras have auto exposure, manual, S and A modes--with a switch for the intelligent photographer to change between them. They are tools, and TTL is a great one to have in the toolbox.

 

 

David I love the creative use of WA distortion in that last shot!!! :wacko:

 

It reminds me of a point that I never bought into in Jim Church's otherwise excellent book "Jim Church's Essential Guide to Composition". He recommends having the diver look away to put a reflection in their facemask to hide the eyes. Had you followed that advice this shot would not have worked. Nicely done.

Edited by UWphotoNewbie

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Chris,

 

Good comments, I forgot about just turning the secondary strobe (red band one) to a manual power setting.

 

Thanks for the kind words on my wife in "Diana Meets Napoleon". Is the main page in DAN's 2007 calendar for November. She tells everyone her measurements are 36-24-36, airbrushed!!! :wacko:

 

Was really a lucky shot as the danged Napoleon Wrasses above the S.S. Yongala in Australia were skittish.

 

Looking forward to Alex's use of iTTL....

 

dhaas

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Hi Everyone!

 

Here is my unsensured rambling on the subject...

 

When I first started out with digital I didn't have the option of manual. For wide angle this didn't matter much as I dialled in the same I did with film and god good results out of the box. However though I got good shots in manual after I homed in on the right exposure in macro, I did loose some oportunities. Another drawback that brought me more headaches was the ****** lying lcd screen. The fix was to use the histogram. All went well! :wacko:

 

A couple of months back I got a sea&sea converter and a couple of Inon 240s. The converter puts the spike of the histogram smack in the middle. This is usually ideal, since we really don't want to change the exposure in raw if we don't have to. Right?

 

If the histogram needs to be a little more to the left just reach out for the ev-controller on the converter and turn it down - the histogram moves slightly to the left. Same with if you need more light on the subject turn to the right.. This has however never been the case and I have set the cameras Ev to -1 now, so that I can use the full range on the controller to go in small increments from normal to -2..

If I encounter a subject that is small/clear/in open water TTL doesn't work (It didn't with film either)... Ok I'll sett the converter to M and shoot away with full "no flawed electronics" to get what I want. But theese cases are rare and manual is a option easy to revert to.

So far however, the TTL system has prooved much more reliable than my 10 years of manual shooting with film and digital. And I have yet to revert to manual once (in this short time). In macro the exposure is usually solely flash and can easily be adjusted so exposure done manually or electronically doesn't matter. The controlling of lightdirection and power differences between the strobes (controlled by strobe placement) are the tools of creative control IMHO, not the exposure itself. Also you retain the light ratio between the strobes at different distances with TTL, with manual you would have to adjust both strobes as distance increased.

 

As a photographer I try to use the tools that best manifest my ideas into a picture (a piece of art), be it film, digital, warm/cold flash, 1-2-3 strobes, shutter arperture, lens etc... More tools - more creative control - more options - more visions?

 

TTL is a tool (a very good one) that does not PRECULDE manual control.

 

TTL or manual? yes please!

 

Cheers,

Espen ;)

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Hey All,

 

Maybe someone can enlighten (no pun intended) me. I'm a Photo J guy and I live and breath eTTL for surface shooting. I shot allot of DVCAM underwater, but am yet to get a housing and strobes for my DSLR's. Help me out here:

 

The general theme is that TTL is good for macro, but not wide angle. I would have thought that would be the reverse. Macro subjects tend to not move around allot, allowing you to chimp your exposure. Wide angle subjects, like big critters, do tend to move around allot making TTL useful.

 

Does anybody make an actual U/W TTL system? The more I look into it, the more I find the need for "converters." One of which looks like it has an "eye" that judges flash exposure. Is there a housing/strobe combination that will let me plug my 5D into a housing, a cord into the hot shoe, and a cord into a TTL strobe?

 

Has anybody had any experience housing an actual 580EX or SB800 flash and using it underwater? Seems like it might be a big pain in the sense that your tripling the number of O-rings that you need to prep and that might fail. But it looks like it might solve allot of the TTL issues.

 

I almost never shoot "raw" strobes on land. I'm a big fan of soft, diffused light. The only problem is, that the minute you put anything in front of that flash head, it's not a point light source anymore and guide number math goes out the window. How do you deal with that without TTL or chimping in the case of subjects where you have a second shot.

 

Phew, that's a lot of questions. I feel like a Trekie that's got Shatner cornered at a sci-fi convention. ;)

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The general sentiment that is pro-TTL for macro, and anti-TTL for WA, is not to do with subjects, but with what works.

 

In general, the entire frame is filled in macro, and the subject is a good part of it, so TTL systems tend to work well.

 

In general, the entire frame is less filled in WA shots, with lots of open water. So TTL systems tend to have a harder time getting the exposure right. Though I find this far less true than it used to be.

 

Many macro subjects too, can swim away and hide quickly, like long nose hawkfish, or tiny baby wrasses, so you may only get one shot at them.

 

I wish there were a TTL system that would just apply the F number guide rule, based on focal distance as measured by the lens, apply the right amount of light accordingly.

 

Yes, there are lots of uw true TTL systems. They are mostly for DSLRS by canon & nikon. Ikelite makes housings and strobes that do proper eTTL or iTTL with their respective cameras. A few canon P&S digicams also work with TTL.

 

I gather sea and sea makes TTL solutions that work with canon & nikon, in their housings as well.

 

Housing a land strobe is not often good, because the color temp is wrong, and the power is not there. But since there are lots of TTL solutions that work fine, it is not a concern.

 

Many or most folks shoot sometimes/often/always with diffusers over the strobes. Not a problem with TTL. Not that much a problem with manual - just adjust by the right number of f-stops...

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"TTL is a tool (a very good one) that does not PRECULDE manual control."

 

I couldn't agree more Espen - but what worries me is that it is all too easy for underwater photographers to become reliant on TTL without ever learning how it operates, its limtations and how to deal with them when they are encountered.

 

In regard to the last poster's question the answer is yes (I admit bias as I'm the British/Irish disributor for Seacam) in that Seacam do produce a wide beam flash unit which has full TTL capability - I have one on order for myself (it has full manual control too!!!) and will give it a thorough testing next year. On this note, the big Subtronics give a very wide beam - so that no diffuser is needed. I've maintained for a long time that the quality of light produced by horseshe shaped tubes and good reflectors is far better than that produced by diffusers - but at a cost. I've also tried an Ikelite DS125 which gives a pleasant output quality too.

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- but what worries me is that it is all too easy for underwater photographers to become reliant on TTL without ever learning how it operates, its limtations and how to deal with them when they are encountered.

 

True.. Most people new to uw-photography have lacking knowledge of how the camera works. One very common example, perhaps more common in the old film days, were the light meter. Many photographers thought this controled the flash meetering. TTL had more followers in the film days for sure, and films dynamic range meant that it had a very good success rate with macro. Photographers understanding how TTL worked compensated by using ev-flashcompensation on -.3 or .7 in wide angle. My own preferance was to use my wide angle flashes with the aperture that equalled full power, but set the flashes to TTL as an overexposure prevantive.. that worked great!

Digital is more tricky because the chance of overexposure are much greater. I think therefore that in order to do well with wideangle todays photographers have to rely on manual for wideangle. Thus, I dont fear photographers will rely too much on TTL in the digital era..

 

Regarding the horse-shoe shaped flash tubes, I couldn't agree more!

 

Cheers,

Espen ;)

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For someone very opinionated, I actually find myself without an opinion!

 

I think that what you produce is what counts. I use digital cameras exclusively now for magazine pictures, when probably as recently as two years ago I was still advocating film for some subjects. However, my epiphany came when Kurt Amsler said to me that if I was not shooting in RAW mode, I was completely missing the point of digital photography.

So, I now find I can do it anyway you want. I rarely take a meter reading with studio flash now and when I recently jumped in with my flashes set to 1/16 power and found myself on top of an oceanic white-tip, even though the dive guide said it was a pity my flashes failed to go off (they were so unbright), I got a very nice picture thanks to the CS2 RAW converter.

So...whatever floats your boat - use it.

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Two and a half years ago I started a discussion to canvass opinion on whether TTL strobe control was necessary for digital underwater photography:

http://wetpixel.com/forums/index.php?showtopic=6199

 

At the time many people were scared to go digital because TTL was not available. The aim of the discussion was to allay their fears, with examples from people who had been through the same worries and had happily come out the other side.

 

30 months on and digital underwater photography has progressed a great deal. First, nearly everyone has switched from film to digital and second many manufacturers have cracked the TTL codes producing reliable converters or TTL compatible strobes.

 

As a result I think it is well worth starting a new discussion to find out how many people are happily using TTL and want to encourage others to do so, too.

 

Personally I still shoot my strobes on manual, but I do this as much because I am too poor to buy some newer TTL strobes!

 

So as a counter to the earlier thread I think it is well worth hearing some more upto date opinions on the advantages and capabilities of using TTL strobes with digital cameras. Please add your thoughts!

 

Alex

 

Hi Alex,

 

I was looking for iTTL protocol details, but now I see it has to be cracked first.

I think this kind of information should be shared by the manufacturer, saving OEM engineer's time.

I can try do crack this protocol, but I have to buy an expensive Logic Decoder first, and it's not feasible for me now.

If you find this information somewhere, please let me know.

 

Have a great 2007 !

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I have been a professional photographer for over 20 years and a diver for even longer, but I have not taken many photographs underwater. I have spent most of my time spearfishing. However, I have just recently started photographing underwater, and I have decided to hang up my speargun.

 

I am in the process of shopping for an underwater strobe, and I am leaning towards the INON Z-240.

 

I am using a Nikon D2X inside a custom built aluminum housing I made in my machine shop. I have a 5 pin Nikonos V strobe cable that attaches to accessory shoe on top of my camera. As I understand it, this connector will not give me TTL capabilities with the INON strobe, I will need to use a ttl strobe connector between the the Nikonos connector and the strobe.

 

I don't think that the manual setting on the strobe will work for me, since I find that the light conditions I have been shooting under, change quickly and dramatically, as does the distance to the subject.

 

So far I have been shooting available light only, and although the results have been pretty good, the slow shutter speeds and wide apertures necessary result in a large number of soft images, not to mention some dark shadows, low contrast and poor color.

 

I've had good luck shooting above water using ttl. so I hope to be able to use the same method underwater.

 

Will I be able to use the automatic settings on the strobe using the 5 pin Nikonos V cable without the ttl connector?

 

The ttl connector is a bit pricey at over $500.00, so I may want to get it at a later date.

 

 

Thanks.

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Well, for what it's worth, I drove up to ReefPhoto this afternoon and picked up a SEA&SEA TTL converter and an Inon Z-240 strobe. Nice compact strobe package.

 

Now I need to learn how to use it.

 

Nice people at ReefPhoto.

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I am switching to SLR and getting a Nikon D-200 and want TTL as I have a lot of otherthings besides manual stobe settings to learn. I am hoping that the new Nexus D200 housing with Inon 240 strobes and the fiber optic cable will provide it. Does any one have any experience as yet?

 

I bought a Heinrich for my Olympus 5060 but I think the reason I flooded it was because of my install. I am leary of tryling anything like that again especially with an SLR.

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I got chance today to use a customers Ikelite 20D camera/housing. We both were set for macro and went looking for small things, it wasn't long before we found a few, after taking a couple of shots with mine (non ttl) I used his, wow! I was getting shots spot on each time with his, where it was taking me 2-3 shots to get spot on with mine, not very important if the subject is not moving but if it is or does then chances are I would have lost out to him. I was even trying to fool the ttl but could not. I went from blue to black background, spot on each time. So to conclude I was very jealous and am going to try and get some kind of ttl for mine!

 

A couple from today:

 

CAY9104.jpg

 

CAY9138.jpg

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