Flash Technique – The 1st and 2nd curtain explained
A DSLR camera provides the option to fire the flash on the 1st or 2nd/rear curtain, which can produces different photographs in the same conditions. This article explains what it means, and how to use it.
The series of pictures below shows a tennis ball falling down, captured with different settings of flash and ambient light. It put in evidence the influence of setting the flash on the 1st or 2nd curtain.