What is a Ratio, and how does it relate to a group?
A4: To answer this question, we need to have a quick look at one of the most important aspects of studio photography (and movie cinematography as well), the concept of Key lights, and Fill lights. Few would argue that shadows are a very important part of the human visual experience, giving us clues as to size, shape, and distance. One of the keys to being an artful photographer is mastering light and shadow, and this is where Key and Fill lights play a big role. To create shadow, and simulate light patterns that our brain is familiar with, it is usually desirable to have one light brighter than the others, just as the Sun is the brightest light outdoors. But lighting a subject with just one light can create deep shadow, and often result in unappealing results. It is often desirable to set some additional lights at one or more strategic locations around a subject, but make them considerably dimmer than the main light. These are called Fill lights. Canon uses the term Ratio to describe t
