Manual optical slave (for digital) w/ETTL-II set up

[Tom Camilleri]

Can a manual flash triggered by a digital compatible (not sensitive to pre-flash) optical slave be used with ETTL-II set-up to, for example, light a background? Are the outputs of the ETTL-II flashes going to be effected at all, or is this determined entirely by the time the pre-flashes have finished?

Thanks for any insights.

[Curtis N]

Theoretically it should work fine. As long as the slave isn't lighting up your subject, it won't affect the metering.

[Tom Camilleri]

Theoretically it should work fine. As long as the slave isn't lighting up your subject, it won't affect the metering.

Thanks Curtis. Since the slave would be aimed at a background the reflected light would not be hitting the front of the subject, so this should work. I will be shooting in M with averaging metering mode and spot metering. Will use a grey card and FEL, then recompose.

Am I correct in thinking that if the slave were to be aimed at the front of the subject, ETTL-II would go through its pre-flash routine and determine output without factoring in the manually set slave, so an overexposure would result? In other words, is all the metering done before the ETTL-II units flash, or are they metering during the flash? If the former is the case it would seem that as long as the slave light did not hit the front of the subject it would work while if the latter is actually the case it would seem that the slave's output would need to be more isolated from that of the ETTL-II units.

[Curtis N]

Am I correct in thinking that if the slave were to be aimed at the front of the subject, ETTL-II would go through its pre-flash routine and determine output without factoring in the manually set slave, so an overexposure would result?Correct.

[Tom Camilleri]

Correct.

Thanks.

[lowcrust]

You could also get a Nikon SB-26 that has a delay mode that fires after your ttl exposure is done.