A simple and nice example of using the Nikon flash system. One remote flash that is fired by the camera's on-board system. In macro photography like this it is important to note that the main on-board camera flash is not contributing to the exposure, it is only triggering the flash. Otherwise the on-board will cause reflections and glare that a remote flash wont. On my Sony A700 this is a problem because you can't turn off the on-camera flash. So a trick I used was to tape a piece of exposed film over the flash. This way the signal light could still trigger the remote flash while not contributing to the overall exposure. (if you do this make sure the camera is set to wireless mode or you will melt the film to your on-camera flash... not ideal). Obviously the Nikon system is better. A quick demonstration using Nikon's CLS with SB-800's and a Nikon D200  ...