Using Sea & Sea YS90DX

Has any one used the YS 90DX without the fiber optic sync cord with a preflash camera in a clear housing?

Can it be set to ignore the preflash and sync with the main flash in a reliable manner without the fiber optic sync cord? I have no use for TTL and want to use the YS 90DX in manual slave mode. How would I focus on a night dive?

For macro photography this WOULD be possible because the output from your internal flash would be seen by the 90DX. One problem though will be backscatter from your interanl flash unless you use THIS TRICK

But for wide angle I think you would be out of luck as your internal flash would not reach the 90DX sensor that would be pointing out and away from the internal flash.

I've tried this. The bottom line is that it'll work if there not too much sun light in the background. It worked everytime in the dark waters of Monterey California, but is unreliable in tropical waters even on close up shots.

Any other advice for these types of shots in the Caribbean with no strobe?

If you are shooting manula why not use a sync cord and turn off the internal strobe. This will fix the backscatter, save camera battery life, and get you the exposures you want.

Nemo