time exposure with flash

akmia5555 · Feb 25, 2009

I am using a Nikon D40,

I'm trying to get the effect that is seen often in Nightclub photography, where the subject is photographed with flash after the shutter has been open for a second. The end result being a solid subject with light trails and motion blur.

Is this something to do with 'Rear curtain sync?'

What do I need to do?

How do I control the shutter speed before the flash?

Solthar · Feb 25, 2009

Close, but not quite. What you want to enable is a setting called 'Rear Curtain Sync', though not all cameras have this feature.

Or you can do the alternate method of grabbing your flash in one hand, setting it to manual, and and hitting the test button right before the exposure ends

.

I highly reccomend reading through your cameras manual, too. I know I've still got my (well used) one sitting right beside my computer!

Big Mike · Feb 25, 2009

It's not hard to do but will probably require some testing before you find the settings that work for you.

It's as simple as using flash with a long shutter speed. I'd suggest using manual mode; set your aperture to F5.6 or F8 and your ISO to 400. Then play with different shutter speeds. I'd start at 1/15 and go down to one or two seconds. You can move the camera around during the exposure to get some 'movement' in the shot.

This can be done with rear curtain sync or not. The difference will be when the flash is fired and thus where the sharp 'flash' part of the exposure will appear. For example, in first curtain sync, the flash fires at the start and then you may get some motion blur after that. So a person walking will looks to have blur going out in front of them...very weird looking. If you use rear/2nd curtain sync...you will capture the blur first and the sharp image at the end...so the blur would be behind the person...making it look like they are going really fast.

So yes, rear curtain sync is probably what you want to use...but it's not strictly necessary.