Ever had trouble figuring out how light would hit your subject's eyes? Just use a black marble!
Photographer Frank Donnino has come up with a dead simple way of figuring out how the catch lights will look in any photographic set-up you could possibly imagine. If you're having trouble visualizing how the incoming light will look on your subject's eyes, just use a black marble to see where the reflections are coming from.
Just watch the brief video below, but it's really a very intuitive idea. The shiny, opaque marble acts like a more dramatic version of an eye, easily showing where the lights are coming from. And then it's just a matter of posing your subject properly—which is a whole different set of challenges.