Sunny 16 Rule

You should learn the Sunny 16 rule because it helps you get better at getting a good exposure in different lighting situations as well as your camera's functions and controls.

You should start at ISO 100 when using the Sunny 16 rule.

A stop is a term used in every aspect of photography to represent a relative change in the brightness of
light. One stop is double the amount of light you had previously.

How many stops brighter is a room if you start with one lightbulb and then add another? One Stop.

All of the settings that represent a "Full Stop" of light.:

f/0.7  f/1.0  f/1.4  f/2  f/2.8  f/4  f/5.6  f/8  f/11  f/16  f/22  f/32  f/45  f/64  f/90  f/128   f/180  f/256