Spring is in full swing, the leaves are out, flowers blooming, the perfect setting for outdoor photography. So, you load up the car with gear and head out to your favorite location, setup the camera and tripod, depress your camera’s shutter slightly to take a meter reading, and uh-oh, for what ever reason the meter’s not working.
Fear not, you can usually use this formula to get you in the ballpark for a decent exposure. It’s called the Sunny 16 Rule and it goes like this; first, set your shutter speed equal to the speed of the type film you’re using; second, use the following aperture settings based on the type of light you’re photographing in. For bright sunlight use f16, slightly overcast skies f11, overcast skies f8, and heavily overcast skies f5.6.
So, for example, if you’re using 200 speed film on a bright sunny day, you would set your shutter speed to 1/250th and your aperture to f16. You can use reciprocity formulas to vary your different settings to suit your needs.
This will get you close to a good exposure (black & white films have the greatest exposure variance, color not quite as much, and transparency film less than sympathetic). The best solution, check your equipment thoroughly before going out, especially on long trips, and carry a handheld meter as a backup.
So go ahead, have fun, and enjoy the beauty of spring.