Leanne, my wife, recently wanted to go rollerskating. There is a rollerskating rink about a 30 minute drive away, but we had never been. While looking up information, I noticed the following photo on one of the pages and new what my next tip would be about. Rear or 2nd curtain sync.
The original and larger versions may be viewed at http://www.flickr.com/photos/7199627@N03/2108070562/ and is from flickr.com user l3xh2k.
I think it is an interesting photo that does a great job of depicting motion, though changing one setting on the camera could have made it a much stronger photograph. This photo is being illuminated with two light sources, the ambient light from the roller rink and the flash from the photographer’s camera. The racers are moving fast enough that the 1/60 second exposure shows some motion within the frame. The flash has provided most of the exposure within the image which has provided a sharp image of the racers, effectively stopping their motion. In this image, the flash fired at the beginning of the exposure, front curtain sync. The results of first (or front) curtain sync are a static image with motion trails flowing in front of the subject. This of course is a little distracting.
Now let’s consider a similiar photo.
This photo and larger versions may be viewed at http://www.flickr.com/photos/photos-martha/422029906/ and is from flicker user photos-martha.
In this photograph, the image is again lit by two sources, the ambient light of the roller rink and the light of the flash. The difference is that in this photo, the flash was fired at the end of the exposure. Using 2nd (or rear) curtain sync this way causes the motion blur of your subject to appear behind the sharp area of the subject in the photograph and enhances the effect of the motion.
In both of these images, the effects could have been exagerated by using an even longer shutter speed.
When I spoke to a few of my photographer friends about front and rear curtain sync, we could not come up with a good example of when you might wish to use front curtain sync. The best answer I could come up with was to use front curtain sync when you are trying to capture a specific point in time and rear curtain sync every other time. In other words, if you are capturing a subject that requires a highly critical point in time capture, then front curtain sync would be your best best as the flash will fire as soon as the exposure begins. Any other time you are going to get a more pleasing image with rear curtain sync. Read your manual to find out how to enable this feature with your camera.
Another note to consider, if your shutter speed during exposure is sufficiently fast enough to stop motion on it’s own, then neither front or rear curtain sync will make a difference either way.
I would like to thank flickr users l3xh2k.and photos-martha for the use of their images with this tip. If you have a question about photography or a subject you would like to see me cover, please leave a comment after the tip.