With flash photography, suggestions are often given that you should use rear-curtain sync. Most often for incorrect reasons. So here is when NOT to use rear-curtain sync flash ... whenever you don't need it. Sounds confusing? Well, let me explain ...
Rear-curtain vs first-curtain sync
Your camera's shutter consists of two curtains that open, and allows the light to hit the sensor or film. This is true for all focal plane shutter film cameras, (as opposed to those with leaf shutters), and true for all digital cameras Read more inside...