All advice you get about photography states that you should avoid shooting in midday sun as much as possible. High in the sky sun creates harsh shadows, can cause blown-out photos and just overall doesn't help create a great picture. Reality is, though, that it isn't always possible to avoid that bright midday sunlight.
The Sunny 16 Rule is an aid for getting good exposure in bright sun. It isn't a miraculous fix, and it won't solve all your midday sun problems, but it will help, and as far as I'm concerned I can use all the help I can get!
Exposure is made up of three factors - ISO, Shutter Speed, and Aperture. The Sunny 16 Rule simply says that at F-stop 16 you should set your shutter speed nearest to your ISO as possible. Once your aperture is set to 16, check out your ISO (for example - set at 100). Next, set your shutter speed so it is at 1/100 (or as close as possible to that). If you move your ISO to 200, move your shutter speed to as close to 1/200 as you can get. If your ISO, for some reason, is set at 800, move your shutter speed to 1/800, or as close as you can get. Get the idea? Keeping these numbers relative to each other in a sunny setting should get you a great exposure. SHOULD.
What if you want a different aperture to get a blurry background? Well, since there are three factors, as long as one is constant you can change the other two and get the same results. To get a wider aperture (smaller f/number) you can change that down and switch the shutter speed to a faster number. Since the aperture controls how much light is let it, changing the shutter speed to control how much is let in for how long will give the same effect. Confused? Hows this:
These f-stops correlate with the following shutter speeds if your ISO stays at 100.
f/16 - 1/125 sec
f/11 - 1/250 sec
f/8 - 1/500 sec
f/5.6 - 1/1000 sec
f/4 _ 1/2000 sec
Now, what about those non sunny situations? Isn't there help for that?
Changing your aperture in these situations will make great exposures:
f/16 for Sunny
f/11 for Slight Overcast
f/8 for Overcast
f/5.6 for Heavy Overcast
f/4 for SunsetFor these f-stops follow the same rule - match the shutter speed nearest to the ISO as possible.
Good luck, and happy shooting!