Lighting Ratios for Portrait Photography

An important concept to understand when dealing with studio lighting for portrait photography is contrast. Contrast is the difference in the amount of light that falls on the dark areas of a scene and the amount of light that falls on the highlight areas of a scene. Due to the latitude of film and digital sensors, it is the photographer’s goal to find the exposure that strikes the appropriate balance between the highlights and shadows. You must begin by deciding the desired “feel” of the final image. If you wish to obscure shadow detail and draw attention to the subject, high contrast lighting may be most appropriate. On the other hand, you may wish to show detail in both the highlight and shadow areas which would require lower contrast lighting. Once you know the effect you wish to obtain, you can begin to identify the proper lighting ratio for the shoot.

Ratio

StopsDifference
Description
1:1
NoDifference
Flatlighting
2:1
1Stop
Generalcolor photography
3:1
11/2 Stops
Generalblack & white photography
4:1
2Stops
Dramaticlighting, low key
8:1
3Stops
Verydramatic, low key

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