Compact Camera TTL

Hi Guys,

just bought my first strobe (YS-01) to link to my Pana TZ10 compact. Started putting everything together and got to thinking, how does TTL work if you have a strobe mask on? or even with some of the Inon Clear Photo film (or cheap alternative from my negatives collection :-) ). The way I understood TTL, the camera preflashes and measures the light levels through the lens, then decides how much power to put in the proper flash. Since the second flash is the trigger for the strobe, and the preflash is blocked, can TTL work?

For that matter, whats best, IR film, mask or both?

Someone please unscramble my brain !

Mooseman

Hi Guys,

just bought my first strobe (YS-01) to link to my Pana TZ10 compact. Started putting everything together and got to thinking, how does TTL work if you have a strobe mask on? or even with some of the Inon Clear Photo film (or cheap alternative from my negatives collection :-) ). The way I understood TTL, the camera preflashes and measures the light levels through the lens, then decides how much power to put in the proper flash. Since the second flash is the trigger for the strobe, and the preflash is blocked, can TTL work?

For that matter, whats best, IR film, mask or both?

Someone please unscramble my brain !

Mooseman

The YS-01 does have a pre-flash cancel mode and generally strobes may have a pre-flash setting, so when the camera pre-flashes the strobe knows that it is a pre-flash and triggers in TTL on the TTL flash The cover over the cameras internal flash helps to prevent backscatter from the internal flash. I used to use velcro over the area and hooked the fiber optic behind it, so the light from the camera would still go through to the strobe. The strobes will use the pre-flash to dump an amount equal to the pre-flash to determine exposure.

Been awhile since I used my strobes like that, but if you hook things up, you should see the strobe give a pre-flash (will be small) then the regular flash. It is fast though

Aaah...that makes sense now, i knew the camera did a preflash and can just about see that, but never noticed the strobe do it, though if its quick and Im not strobing myself I may never have noticed it. Ill go home and shoot myself in the face just to check :-)

Im assuming the same be true with the clearfilm system, with the IR wavelengths being enough to trigger the strobes flashes but not allow backscatter by blocking the visible light from the full flash.

Beginning to make sense now, cheers !

Other question still stands though, is it better to use the mask, the Clearfilm idea, or a combination of both ?

Moose

What housing do you have? The ikelite, or 10 bar, or is there another?

What is better to use just depends on conditions.

If the water is extremely clear, you could use a flash diffuser, and let some of the light through, and add the external strobe light to it.

But if it is not perfectly clear, you'll get more backscatter from that setup.

I've even just used black duct tape, often to secure the fiber and block the direct flash light.

In order to minimize stray flare, you want to watch for the camera flash light reaching out to the port. Hopefully your housing has a black foam doughnut that fits between the lens and the sides of the port, to block that light. Make sure it is well seated.

Cheers guys,

Ive got the Panasonic housing for the TZ10, cheap and cheerful. Not as well made as the Fuji housings Im used to but it gave me no troubles in Bali last year. Its not going to that easy to attach the fibre optic unfortunately as the housing diffuser has to come off for me to be able to add the macro lens. Looks like a bit of experimentation required.

I did notice a bit of lens flare last night with the macro lens on, mostly on the lens ring, Ill have to add the masking papers Inon gave me with the macro lens to the barrel of the camera lens.

Things arent as simple as they should be, but its a good excuse for some man time to experiment !

Moose