Rear Curtain Synch and Off Camera Flash

When you are dragging the shutter do you set the camera to rear curtain synch when using off camera flash. I am using total manual on the flash and camera.

How are you triggering the off-camera units?

You can't use 2nd curtain with the Canon wireless flash system, or with a PC cord or radio remote system.

The only way I know of to use 2nd curtain off-camera is to use traditional optical slaves to trigger the remote units while a hotshoe-mounted unit is in manual mode.

2nd curtain sync is not always necessary or desirable when dragging the shutter. Tell us more about the scenario you're trying to shoot.

I am using cyber synchs to trigger the Sunpak 120J off camera. I have dragged the shutter before and never thought about using a rear curtain synch.

I came up question because I was watching an instructional video and the instructor was using a SB 900 off camera and using rear curtain synch.

Most of the scenarios I drag the shutter is for portraits in low light when I am trying to bring in the ambient.


Thanks Curtis !!!

Curtis N wrote in post #8514149
How are you triggering the off-camera units?

You can't use 2nd curtain with the Canon wireless flash system, or with a PC cord or radio remote system.

The only way I know of to use 2nd curtain off-camera is to use traditional optical slaves to trigger the remote units while a hotshoe-mounted unit is in manual mode.

2nd curtain sync is not always necessary or desirable when dragging the shutter. Tell us more about the scenario you're trying to shoot.

Just to clarify, the flash mounted in the hotshoe has to be ETTL compatible, too. A non-ETTL flash sitting in the hotshoe won't fire on 2nd curtain sync, either.

If the subject is not moving, why do you want rear sync?

bobbyz wrote in post #8514425
If the subject is not moving, why do you want rear sync?

Thats what the guy said in the video *L* He used rear curtain. Maybe it is a Nikon CLS thing.... He used a Nikon with the SB900. He really did not say why he was using rear curtain..

Like I said I never used it but when it came from someone who produced a video I thought " Hey maybe I am doing something wrong"

PacAce wrote in post #8514397
Just to clarify, the flash mounted in the hotshoe has to be ETTL compatible, too. A non-ETTL flash sitting in the hotshoe won't fire on 2nd curtain sync, either.

YEP this is total manual so ETTL is not involved.


Thanks !!!

What Leo meant, which I neglected to specify, is that only a dedicated flash unit (E-TTL compatible) will do 2nd curtain sync. Your garden variety hotshoe flash such as a Sunpak 383 or Vivitar 285HV won't do 2nd curtain, even if it's on the hotshoe.

YEP Got it... I thought I was missing something.

Thanks for everyone input

I'm glad you asked this question - I've been meaning to look into this for some time. In one of Scott Kelby's books he has a page called something like "Rear Curtain Rocks - Why You Should Use It." He advocates setting that to be your default all the time.

This may be slightly off topic but while on the subject of rear curtain... if you were using a reflector, would rear curtain negate its effect? I've wondered about this, as if the flash fires at the very end, I would think there wouldn't be enough time to get the light from the flash to bounce off the reflector into the scene.

MonteMama wrote in post #8514946
I would think there wouldn't be enough time to get the light from the flash to bounce off the reflector into the scene.

Light travels at about 186,000 miles per second. You can estimate the distance and do the math if you want.

But the short answer is, as long as you're shooting something on the same planet, the time required for light to reach your target is insignificant.

MonteMama wrote in post #8514946
I'm glad you asked this question - I've been meaning to look into this for some time. In one of Scott Kelby's books he has a page called something like "Rear Curtain Rocks - Why You Should Use It." He advocates setting that to be your default all the time.

Any reason he mentions to use it all the time?

As I recall McNally's reasoning, at relatively fast shutter speeds it won't matter. Canon cameras actually enable 2nd curtain at 1/30 or 1/60 depending on the model. Faster than that, and it will use 1st curtain regardless. I'm not sure about the Nikons.

So having 2nd curtain set all the time means you can quickly adjust shutter speed to capture a moving subject. You won't miss the shot while you fuss with the menu settings.

Many flash users employ 2nd curtain sync without having much of an idea regarding what it really does, thus when it really makes any kind of difference.

Me, I rather set the flash to high-speed sync than 2nd curtain, since I see more use for the former than the latter.

bobbyz wrote in post #8515337
Any reason he mentions to use it all the time?

I read it a long time ago - but I believe it had to do with trails falling behind a moving subject instead of in front of them?