Sunny 16 Rule

How to expose in daylight without a light meter? Use the Sunny 16 rule! If you don’t know how to use your meter, or it doesn’t work, or you don’t have one, this trick is a life-saver.

“On a sunny day set aperture to f/16 and shutter speed to the [reciprocal of the] ISO film speed.”

Let me translate: f/16 is an aperture number on the lens, shutter speed is on top, and ISO is the number printed on the film. For example, Ilford Delta 400 has an ISO of 400. [I’ve posted articles explaining aperture and ISO for those who are interested]

An example of the Sunny 16 Rule would be: For film with an ISO of 100, aperture at 16 and shutter speed at 1/100 or 1/125 (depending on your camera)

ISO 400 would be f/16 at 1/500 (unless your camera miraculously has 1/400)

Here’s a handy daylight exposure guide guide from the inside of some Fuji Provia (ISO 100):

You can read more about how to use the Sunny 16 rule and adapt it for various situations here.

Wikipedia: At or in this place: Stop here for a rest.