Freezing action with the flash

This is one of the last strobist exercises, where the camera is either zoomed or moved as the exposure takes place, and the flash will freeze a moment of it.

Because the flash duration is extremely short, maybe 1000th of a second or less, the rest of the exposure may blur, but that moment will be caught clearly. Because of this Joe McNally recommends using trailing curtain flash, so the clear part is at the end of the apparent movement instead of at the beginning. It makes a lot of sense. Additionally, in many automatic settings, the shutter speed will revert to 1/60th of a second when the flash is applied, trying to negate this effect. You may need to shoot in manual or trailing curtain flash mode to do this.