Sunny 16 Rule
In photography, the Sunny 16 rule is a method of estimating correct daylight exposures without a light meter. The Sunny 16 rule can also aid in achieving correct exposure of difficult subjects such as a snowy scene in bright sunlight or photographing a black tire. All cameras are calibrated to meter for an average tone. In the world of photography that tone is called 18% neutral gray. When we point our cameras at either a black tone or white tone they will always be visually rendered, in the resulting image, as a gray tone rather than black and white (try it some time using your camera’s live view mode). That is when the Sunny 16 rule kicks in.
This same rule kicks in when photographing a full moon on a clear night. Since the moon is equally as bright as the earth at noon you can hand hold your camera and get a great shot of the moon, craters and all!!!
All settings can only be set on camera’s that have a manual mode. The basic rule is, “On a sunny day set the aperture to f/16 (this is where the “16” of The Sunny 16 Rule comes from) and shutter speed to the closest number to the ISO film speed.”For example:
* On a sunny day and with ISO 100 film in the camera, one sets the aperture to f/16 and the shutter speed to 1/100 or 1/125 second (on most cameras 1/125 second is the available setting nearest to 1/100 second).
(This would be used when using the kit lens)
* On a sunny day with ISO 200 film and aperture at f/16, set shutter speed to 1/200 or 1/250.
(This would be used when using a telephoto lens up to 200mm)
* On a sunny day with ISO 400 film and aperture at f/16, set shutter speed to 1/400 or 1/500.
(This would be used when using a 300-400mm zoom lens)
Adapted from Wikipedia
SUNNY 16 CHART
Aperture Lighting Conditions Shadow Detail
f/16 Sunny Distinct
f/11 Slight Overcast Soft around edges
f/8 Overcast Barely visible
f/5.6 Heavy Overcast No shadows