DS-TTL II with the S&S YS-D1

Can anyone help me understand the difference between DS-TTL II and Slave TTL in regard to the YS-D1? The manual is confusing in regard to fiber optic triggering.

It seems that DS-TTL II allows some exposure control via the dial while the slave TTL does not. If that’s the only difference, I don’t understand why there would be two options and why I would ever use Slave TTL rather than the DS-TTL II.

Perhaps Slave TTL is only used on a camera that does not preflash, but I don’t see how you could get TTL without preflash.

Also the last bullet under the DS-TTL II section says “There may not be any effect obtained from compensation with the light level control dial depending on the shooting conditions and the camera settings.” Again, I’m not really sure what that means if the whole purpose of DS-TTL II is to allow for exposure compensation.

Can anyone shed light on this (pun intended)?

Slave TTL would be for situations where there is no preflash such as:

Cordless ( line of sight ) slave triggering from another strobe - not very reliable underwater but works on land

Cordless slave trigggering from film camera

As long as the master flash/strobe is TTL cabable the slave will quench to provide TTL exposure as well.

HTH

We look at it also as sort of a "compatiblity" mode should a camera in the future not be compatible with DS-TTL, slave TTL should work.

We don't think it's quite as accurate, but at least it's there. And it has a really cool blue light that shines... ;-).

Jack

Thanks! I've played around with them above water and the light level control seems to work great in the DS-TTL mode. I'll be trying them UW next month.

Perhaps Slave TTL is only used on a camera that does not preflash, but I don’t see how you could get TTL without preflash.

Maybe it is for film SLRs that has TTL w/o preflash? Maybe the trend is that they will meter the amount of light captured in real-time via output from the imaging sensor and shut off the internal flash in real time, as opposed to the SLR days where the sensor measures the light bounced off the film.

who knows what they will come out with. back in 2003 when I got my 5050, the only strobes available were available were manual ones. I was thinking why can't they invent a TTL one where the strobe just emulates the duration of the intensity of the camera's flash...and many many years later, voila, they invent it....plus shutterless camera, just capture the image straight from the sensor

I am also still struggling with this issue.. by the way I am going to use YS-DS1 with mirrorless LUMIX GX1 with nuticam.

any special requirement for using the S&S YS-D1 with the OLYMPUS OMD in a Nauticam Housing?

I am also still struggling with this issue.. by the way I am going to use YS-DS1 with mirrorless LUMIX GX1 with nuticam.

I set it on DS-TTL II and had very good results with my 7D. The "other" slave seems to be for non-compatible cameras. I did have the lock up issue that was supposed to be fixed by the recall. Backscatter gave me two replacements. I'll test them in real water next month.

Thanks, its clear now. I too just used the TTL ii which worked for me in my initial work.