On-Camera light shines in the middle of the subject's face and gives the shot that burst of much needed light. During those times where too much harsh light takes away from the shot but no natural light is available, an on-camera light really shines, literally.
When are on-camera lights best used? Outside day shots in the middle of winter offers very little sunlight. On-camera light offers a solution to this problem, and the problem of filming indoors where the light isn’t sufficient such as in a church or while filming family memories during holiday events.
Effective on-camera lighting system is more than turning on the light that is built into the camcorder. It is okay to use that, but on-camera lighting has more to do with a technique and less to do with the light itself. It involves three different, yet basic, elements; the light, how it is mounted, and from where it gets its power.