DS-TTL for a Sea and Sea strobe

[Calinectes]

I have a Panasonic TZ7/ZS3 in a panasonic oem housing. I just got a S&S YS-01 strobe and was working on adapting the fiber optic cable to the housing. I know Inon makes a $30 cap for this but I figured I could use the generic velcro end and just plaster it on the housing. The housing doesn't have a flat surface anywhere to put the velcro so I mounted it to the diffuser.

Here's the question....... Does anyone know what the strobe "reads" to adjust DS-TTl? My problem is that the TTL doesn't seem to work through the diffuser, but does work (no changes in camera settings) when I hold the cable directly over the flash. Should it work through the diffuser? Did I do something in the mounting to block it or does the diffuser mask the signal needed for TTL?

 

[bvanant]

My understanding (which certainly may be NOT TRUE) is that the camera strobe sends out a pulse to the strobe, the strobe sends out a tiny pulse, the camera reads the return then fires the camera strobe at the appropriate power through the cable to the strobe that then sends out the correct pulse to the scene. Given that, I would have thought that if the diffuser is in the way, you would probably be overexposing your scene.
Bill

 

[Calinectes]

Yep... overexposure is what is happening when I trigger the strobe through the diffuser.

 

[Puffer Fish]

My understanding (which certainly may be NOT TRUE) is that the camera strobe sends out a pulse to the strobe, the strobe sends out a tiny pulse, the camera reads the return then fires the camera strobe at the appropriate power through the cable to the strobe that then sends out the correct pulse to the scene. Given that, I would have thought that if the diffuser is in the way, you would probably be overexposing your scene.
Bill

Bill, you have it correct... it actually uses time. It times the first tiny flash, until it gets enough light, then fires the big flash the same amount of time (or some ratio, of the two).

The preflash is not a very strong signal and it has to get both the start and end very, very accurately to work.

The typical failure is to have it see the start of the preflash, but not see the end, and that will cause the S&S to just fire the complete flash.

There are two typical causes for this... not a good signal.. which results in it starting, but not shutting off (as the off part is harder to detect.... or one is getting some of the sea and sea strobe preflash in the light sensor going to the sea and sea strobe... which then does not turn off.

It is critical that it gets as strong a signal as possible, and that as little light from itself gets into the fiber optic cable...