Canon 7D using sTTL optical sync. (Sea&Sea YS110a)

Hello,

I have an Aquatica A7D housing with optical sync cables to Sea&Sea YS-110a strobes.

When trigging in manual mode it works fine, but when trying the strobes set to Slave=On, and Mode=TTL,

I only get the strobes to flash at full power thus giving extremly overexposed pictures with TTL.

It is as if the camera does not detect any flash during the pre-flash sensing and then hits with all the flash power it has got.

I think this could have to do with settings on the camera, but I am still learning how to use this system, so if anyone knows or has any idea on what settings to use on the Canon 7D camera to activate sTTL (TTL with optical sync cords) I would be grateful if they could share that information. I think even if you do not have Sea&sea strobes, but use optical sync coords to your strobes, the settings on the camera would be the same, as they should be for me, and thus those settings would be useful info for me.

OT: The Aquatica A7D housing I got was upgraded from all reviews I have seen. The start/stop button is now more accessible than before as it has been moved forther to the edge.

Thanks,

Joakim

Mine works fine.

Slave = On, Mode = TTL, Light level control dial = FULL

And try "AF-assist beam firing = off" in camera menu.

do you have the camera set on TTL in the flash menu? you can choose between manual output and ttl.

Setting P (Program) or M Manual mode

Flash Control:

Flash Firing: Enable

Built-in flash func. setting:

=======================

Flash mode: E-TTL II

Shutter sync.: 1st Curtain

E-TTL II: Average

Wireless Func: (Picture of External flash only)

Channel: 1 ch

Firing Group: Picture of external flash + (A+B+C)

Everything else below is greyed out

@Escape:

I turned AF-assist off , it looked like it turned off some AF pre-flashes, that triggered my YS-110a strobe...

If I set the strobe to:

Slave= On and Exposure =Full,

Then

Setting Mode= TTL:

...

The flash will not trigger since the camera sensor already has enough light in some cases without flash.

Long exposure times for instance will in some cases cause the flash to be all black in the picture you shoot.

As long as you keep the exposure time around 1/60 it works fairly well

Changing the exposure to be more over exposed can actually trigger the strobes. Also reducing ISO to 100-200 helped (since then you need more light).

It seems to work now... Changing flash exposure in the camera also changes the amount of light from the external strobe as it should. Yey!

What seemed to affect this the most was: In P,CA,Tv modes: 1/Exposure 2/exposure time; In M, Av modes: 1/Exposure time, 2/ISO

Bulb: Not working

Setting Mode = Manual 2:

The strobe fires by the pre-flash, and is of no-use to the actual picture

Setting Mode = Manual 1:

The strobe fires when the shutter is open ignoring the pre-flash, and the flash power can be controlled manually (but it is not TTL)

Setting P (Program) or M Manual mode

 

Flash Control:

Flash Firing: Enable

 

Built-in flash func. setting:

=======================

Flash mode: E-TTL II

Shutter sync.: 1st Curtain

E-TTL II: Average

Wireless Func: (Picture of External flash only)

Channel: 1 ch

Firing Group: Picture of external flash + (A+B+C)

Everything else below is greyed out

I think I am seeing two problems:

1) You have set the camera Wireless Func in the mode for controlling Canon Ettl compatible flashes. In order to work with Sea&Sea YS-110a strobes in DS-ttl mode, you have to disable this (Wireless Func. -> Disable).

2) You should use 'M' mode for the camera to have full control of the exposure, with the flash pop-up. That means: pick you preferred ISO, shutter speed (<1/250) and aperture. The TTL metering capability of the pop-up flash will expose correctly according to the scene with reference to these settings.

The Sea&Sea DS-ttl works by repeating the pop-up flash so the camera even does not know the light is not of its own. You can try setting camera to M mode, pop-up its flash and play outside of the housing to ensure its TTL works, and is controllable (flash exposure +/-). After things work fine then you can try with the Sea&Sea strobes connected.

Edward Lai

Hello,

My name is Fabian and I'm new here

I have got nearly the same problem like Joakim has/had

I've got an EOS 7D in a Nauticam Na-7D housing since last spring and a Sea&Sea 110 strobe (NOT an alpha, but should work as well persuant to the product info; bought the strobe in 2008)

I want to use the DS-TTL function of the strobe by an optical cord but it simply doesn't want to work.

On the strobe I've chosen TTL and slave: ON by full power like it is told everywhere.

chosen camera settings:

flash mode: E-TTL II

shutter sync.: 1st curtain

E-TTL II: Evaluative

Wireless Func.: Disable

I shoot in Av or M Mode.

The problem is the following:

If i want to shoot with DS-TTL the ys 110 flashes with maximum power and thers is no recorded picture. -> black backscreen

At the moment there are two options how i can take pics:

1) I shoot completely manual by taking 1/128 flash output on the cam and taking Manual 2 on the YS 110 with choosing the output directly on the strobe.

2) I set the strobe on TTL;slave and full power like I would do it if I could use DS-TTL.

But on the camera my flash control settings are Manual flash and I choose the flash output by hand for every situation from max. 1/1 to min. 1/128 in the menu. My YS 110 is able to mimic the flashs from the integr. strobe very well. (apart from that the YS 110 very often only works on the 2nd or 3th try^^, - that's another problem I've got (also by option 1))

But isn't that the same like shooting in DS-TTL?

So why does the YS 110 mimic the intern flash right if I choose the intern output but doesn't if eTTL II chooses it? :S

Could someone give me hint to solve this problem?

Thanks,

Fabian

I've got an EOS 7D in a Nauticam Na-7D housing since last spring and a Sea&Sea 110 strobe (NOT an alpha, but should work as well persuant to the product info; bought the strobe in 2008)

I could be wrong, but I thought the non-Alpha does not work with TTL in the recent Canons....

I could be wrong, but I thought the non-Alpha does not work with TTL in the recent Canons....

I didn't thought that there could be no compatibility by using optical sync.

because I don't think that the flash by eTTL has a different appearence like if I would choose it by hand in the cam menu - or not? or does the eTTL flash flicker or something like that? (i don't mean the pre-flash(s) or the AF adjusting flashs)

I mean is there a difference between the manual and the cam controlled flash?

but I think I will check that in a few days if I maybe buy a new YS 110 alpha. maybe it works then.

I would concur as to what Edward says above.

In the Flash Func Settings the

Wireless func. -> should be set to disabled.

With this enabled your interneal flash is sending pulse flashes to the slave Canon speedlights to measure/set them up. This is intended for Canon speedlights to talk together to detect exposure and set flash ratio's.

Turn it off and have a go with that.

Cheers

Ben

the wireless thank was already disabled.

But thanks to both of you.

I didn't thought that there could be no compatibility by using optical sync.

because I don't think that the flash by eTTL has a different appearence like if I would choose it by hand in the cam menu - or not? or does the eTTL flash flicker or something like that? (i don't mean the pre-flash(s) or the AF adjusting flashs)

I mean is there a difference between the manual and the cam controlled flash?

 

but I think I will check that in a few days if I maybe buy a new YS 110 alpha. maybe it works then.

The YS110 (not alpha) are notoriously unreliable when trying to do TTL with a fiber optic. On the alpha, I have no problems at all.

Bill

Thanks Bill,

Than I will by the new one