Considerations of A Good Monolight
Monolights are photographic flashes and therefore carry some of the same considerations as a standard flash unit. A primary concern is guide number. Each monolight has a guide number specifying its range at certain film speeds. A common misconception is that the watt-second measurement is an indication of light output. It is not; it is a measure of electrical energy. While the electrical energy used in firing the flash is usually the most significant factor, light output is also affected by the efficiency of the flash tube and the capacitor.
In addition to power output, monolights have other, special considerations as they are meant to be used for large-scale, studio work. Portability, consistency, feature set, parts availability and cost are prime considerations in monolights.
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