Subjects on sunny beaches require an f/22 aperture, according to the Sunny 16 Rule.
A camera's aperture is like a mechanical iris: the wider it opens, the more light is allowed in. By controlling the size of the aperture in conjunction with the shutter speed, you allows just the right amount of light to come into contact with the film for exactly the right amount of time. A rule of thumb is the "Sunny 16 Rule." This states that the appropriate aperture size, or f/stop, is f/16 when the shutter speed is the reciprocal of the film speed, or ISO, and your subject is in bright sunlight. From this starting point, photographers can determine the correct f/stop for every other lighting situation.
Instructions
1. Determine the amount of light that is falling upon your subject. Photographers often use descriptors such as "full sun," "slightly overcast," and "open shade" to describe different lighting conditions.
2. Refer to an exposure chart to see how many stops above or below f/16 your lighting condition requires. A negative number indicates that you must open your aperture that many stops wider. For example, an exposure value of -3 means to open your aperture three stops, which would be f/5.6. A positive number indicates that you must stop down, or make your aperture smaller, by that many stops. Many photographers commit this chart to memory. These exposure values are valid only at the shutter speed that is closest to the reciprocal of your film speed.
3. Determine the most effective shutter speed for your subject. Fast shutter speeds allow you to freeze motion or open your aperture wider to throw more of the background out of focus.
4. Open up your aperture one stop from the estimated exposure value for each incremental increase in shutter speed. For each incremental decrease, close your aperture by one stop.
Tags: your aperture, shutter speed, many stops, your subject, amount light, aperture stop, each incremental