Paul C. Buff, Inc. Technical Forum

No, Canon speedlites don't have an optical slave mode.

Funny how 500 dollars speed lite can't while 359 dollars light can ;)

I should had bought ab 2 years ago :roll:

Just be aware that this may not work if you decide to use the speed light in your camera's hot shoe and expect all other lights to slave off that flash.

If you don't think you'll ever intend on doing this, don't get more confused and skip the rest.


But if you do, you may find other slave flashes work intermittently if at all. (i.e. your photo comes our very dark or black as if no flashes fired)
Basically, ETTL must send out a pre-flash to allow the camera to properly meter the scene prior to firing the flash at the proper power to expose that scene.

This pre-flash can kick off your slaves.
By the time the full-power flash is made by the hot-shoe speed light and your camera exposes the sensor, all of your flashes have finished firing.

This issue had me confused for quite a while, a few years ago, until I figured out what was going on.
Since it was somewhat intermittent, it was hard to pin-point until I realized how the hot-shoe flashes worked on my camera.
Just wanted to save the headache in advance.

** If this becomes a necessity, I think the Canon speedlites can be put in full manual to turn off the ETTL pre-flash metering. This will allow the hot-shoe flash to fire only the exposure flash and then will work with slaved strobes.

Thanks for the tip

You can accomplish the same thing with the pop-up flash on your Canon. Or even a point-and-shoot camera, for that matter.

What's the trick to get slave b1600 to flash when using boom about 9 foot high with a 70 inch octagon softbox? I know bouncing on white ceiling may work but it didn't for me. So only option I have was using the sync cord. I was curious on how you would get it to flash without the cord or wireless trigger?

The eyes are optical, which means they have to see the master flash. This does not mean direct line of sight, but bounced flash often works as well. If the master flash does not have enough power to bounce sufficient light into the slave eye, then it will not trigger. You can get accessory optical slave eyes that attach to a sync cord. This will allow you to reposition the eye so it can better see the master. In a small studio, this would be sufficient, however, if you are ound other photographers or in bright light, radio remotes are still advantageous.

Thanks for the tip

Notice that this product doesn't work with the 580EX or 580EX-II. You might be able to find something similar that would, but if you're going to spend money and add another device to your speedlite, why not just get a radio trigger? It will be a much more useful purchase. I use the Cyber Commander with CSR+ and CSXCV and am very happy. I also use the Phottix Strato 4-in-1 which is great - and the Strato II is now out and looks even better. Neither Strato will give you remote control of power settings though. Cyber Commander+Einstein is the best.