In This Chapter
D200 flash basics
Flash sync modes
Flash exposure modes
Flash exposure compensation
Using external flash
Conquering available light
As a photographer, light is one of your basic tools. The quantity and quality of the light you work with has an effect on every other aspect of your photography. The amount of light available controls whether you can make an exposure at all, how well you can stop action, whether you can slow down a shutter enough to use movement blur creatively, and how you apply selective focus. The distribution of light affects the tonal values and contrast of your photo. The color of the light determines the hues you see.
In many ways, photography (light writing in ancient Greek) depends as much on how you use light as it does on your selection of a composition or a lens. Great books have been written on working with lighting; for this field guide, I concentrate on some of the nuts and bolts of using the lighting tools available for the Nikon D200 digital SLR.
Light falls into two categories: continuous light sources, such as daylight, incandescent and fluorescent light; and electronic flash. Both forms are important.
Electronic flash illumination is produced by accumulating an electrical charge in a device such as a capacitor, and then directing that charge through a glass flash tube containing a gas that absorbs the electricity and emits a bright flash of photons. If the full charge is sent through the flash ...