How can I drag the shutter on a Canon 50D (or any Canon body)?

Question

I want to drag the shutter (second curtain sync) on my Canon 50D using either a speedlight, or via a wireless remote flash.

The 580 EX/EXII will trigger when the shutter opens, and again when it closes. I only want the second flash before the shutter closes, I don't want the first (e-TTL?) flash.

Secondly, I can't find a method of setting second curtain with a Pocketwizard attached.

Any suggestions?

Asked by Chris

Answer

Unfortunately there is no way to get a Canon DSLR to actually send the flash signal when the shutter is about to close! Canon flashes know the shutter speed so they can delay the firing. When using a flash that doesn't talk to the camera you can't get second curtain sync. However, when using a Pocketwizard, you can set the Pocketwizard to add the appropriate delay to get the flash to fire with the second curtain (I think only some models e.g. Pocketwizard multimax allow this).

When set to second curtain sync the first flash is actually before the shutter opens and is for metering purposes (e-TTL as you suggest). To turn this off you'll have to use the flash in manual mode.

Answered by Matt Grum

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