How to check if a camera is compatible to TTL function

[Hashsaz]

Hi,


I've been touching the photography line in couple years. All the equipments I used are mainly recommended by others or from google research. Recently, I've upgraded 2 strobes and these questions come to mind:


how do we know if the TTL function of a strobe is compatible to one's camera or housing?


Some companies show their strobe's compatibilty list, as well as the model of the camera housing but usually they shows the housing that were produced by its company, so, how do we know if our housing (other brand) is fine to use the function. Or, TTL is independant on housing?


Hope anyone can answer my question, sometimes it sounds embarrasing when you can snap a good uw photography (maybe) but you don't know why it works especially when someone ask you for advices to get any camera or uw equipments. or you have a good equipment, but due to imcompatibility of a camera,which leads terrible results and makes your day terrible when you view back your photo after a dive trip.

 

[vladimir]

I'm no expert, but until you get better advice you can try this. It was Jim Church's method of testing TTL on a NikonosV, so I don't know how relevant it is to your camera.

I am assuming that you have an external strobe that is attached by a synch cord and fires when you snap a picture. The only question is whether the flash is being modulated by the camera's TTL.

Step 1. Open your lens all the way, to F2.8, or whatever it is. In aperture-priority mode, with the strobe pointed directly into the lens, take a picture. Your strobe flash should be minimal and it should cycle (recharge) immediately.

Step 2. Close the aperture (f22). Cover the lens with a lens cap and take a picture. The flash should be very bright, and the strobe should take longer to cycle.

 

[bvanant]

Most modern strobes have some sort of TTL emulation built in if they can be fired via fiber optics. Most strobes can be made to work with most cameras (the biggest issue is the number of preflashes that the camera uses). That being said there is also a dependence on the housing, for example most Ike housings have no way to use FO strobes so you need to be careful of that. Give us an example and we can tell you how to test. In general I set up a yellow rubber duck and shoot it at f2, f4, f5.6, f8, f11, f16 and f22. If all the shots look the same then TTL is working. If not then not so much.
Bill

 

[Hashsaz]

Thanks for the respond.

I knew how to test on TTL maybe my question confuse you guys. The question is, like when you visit to a camera shop, let's say you are buying a dslr. Based on its given specs, is it any way to check whether it's working with TTL? As this is common procedure, you will get a cam first, then will only go for the housing. Lastly, you can only try on your strobe, with sync cord or FO. So definitely you won't give yourself a try at the cam shop, kinda awkward too if u bring all the equips, but you are not taking it if it's incompatible.

recently, there's someone posted a thread asking about instability of his 2 strobes after he upgrade his camera from canon to epl-2. Kinda waste if you bought everything and how excited you're when you'd like to try on it, but bring you a disappointed result.

i believed all the uw photographer love to know the answer, especially those who thinking for upgrading.

thanks.

 

[bvanant]

Canon, Nikon, Sony, and Olympus all have their own versions of TTL, and I don't think there is a current DSLR that doesn't have TTL capability but they are all proprietary to the manufacturer. For example I can not use a canon flash on a nikon camera and get TTL function. That is what is happening between the camera and the strobe in a housing, not that the camera doesn't run TTL (it certainly does) but that the strobe cannot figure out how to use the TTL signal from the camera.

TTL works sort of like this. The camera shoots out a very low power flash (or flashes) and then monitors the return light from the scene. The camera then adjusts the flash for the appropriate power, fires the flash at that power and records the picture. The bit about "adjust the flash" is the hard part and they keep it secret.
Bill

 

[Puffer Fish]

Hashsaz. This can be one very trying issue to resolve. Even within a camera line, you can get different responses with different camera's in the line.

But a few basics:

1. Ignore the housing..this is an issue between the camera and the strobe.

2. Know how you plan to take images. If you are new to underwater photography, this can be difficult to do, but at least look at images and decide what you like. My panasonic GH1, for example, works well until the strobe power gets something over 60%, and then looses sync, so as long as I don't want all the flash power, it works well. My Pany GX1, does not have this issue.

3. Research your favorite brand of camera. The Oly xz-1, for example, will not work in ttl with Sea and Sea strobes, but it will with Inon. However, it has manual strobe control (in manual mode) and works really well with Sea and Sea in manual control. The LX-5 (which I understand has a flash system made by Oly), actually does sort of work in TTL, but does not have manual strobe control. Move up the the interchangeable lens camera's, and Oly does not work with Sea and Sea, but Panasonic models vary in how well they work (but they mostly work).

4. Canon are a very known issue, and I believe all work well (at least the 5 models I have). Not tried and don't own any Nikon, so cannot tell if there are any camera's that have issues.

5. If you pick a camera you think you want and then do some homework.. you may have to look a few places, but odds are, you will find any issues. It may be that your options are limited, it may be that every strobe will work.

 

[Tigerman]

1. Ignore the housing..this is an issue between the camera and the strobe.
...

That actually depends on wether or not the housing has TTL circuitry in it and wether or not the strobes is from the same manufacturer as the housing..

 

[Puffer Fish]

That actually depends on wether or not the housing has TTL circuitry in it and wether or not the strobes is from the same manufacturer as the housing..

Correct, I should have made it clear I was talking about sttl or whatever they want to call optical TTL.

Hard wired is a very different issue, and requires some very specific knowledge about the camera, the housing connections and the strobes. I've never seen anyone buy a hard wired system without understand all the rules for that specific system, but I guess it is possible. From experience, I would guess that the vast majority of hard wired people are using manual control, or have a dedicated system. I kind of admire anyone going to the Heinrichs solution, and other than that, one is pretty much left with the Sea and Sea or Ikelite options.

Note: Don't have a clue about any Inon choices for hard wiring.

 

[Tigerman]

You can get optical TTL converters for Ikelite housings, not sure if they go with Inon though.

 

[DazedAndConfuzed]

If the camera has a single pre-flash, I presume it should automatically be compatible with all the general optically fired TTL strobes. It usually are the multi-pre-flash-firing internal flashes that gives external strobes trouble.