To understand how Zone System theory applies to exposure, let’s first consider the different types of light meters available and how they function.
Light meters come in two general types: meters that measure what is called incident light and meters that measure reflected light.
Incident-light meters measure the light that falls on the subject from the source of light (see figure 5.1). Incident-light meters are especially useful in lighting studios or on movie sets where the contrast can be controlled with fill-lights or reflectors. Under those conditions, your primary concern is to make sure that the amount of incident ...