Tips > Exposure > Sunny 16 Rule

You don’t need a light meter.

You can set the exposure using the Sunny 16 Rule.

The Rule

In bright sunlight, set the lens opening to f/16 and the shutter speed to the reciprocal of the ISO.

An Example

You're photographing in bright sunlight.

What's bright sunlight?

Use the shadows to evaluate the brightness of the sun and sky.

In bright sunlight, shadows are dark with sharp edges.

Let's say you've set the ISO to 200.

For the correct exposure, set the lens opening to f/16 and shutter speed to 180.

1/180th is the closest shutter speed to ISO 200.

In other lighting situations, use the table below.

Light	Exposure	Shadows
Sunny	Shutter: Reciprocal of the ISO Lens opening: f/16	Dark with sharp edges
Slightly overcast	Add 1 stop to f/16: f/11	Bright with fuzzy edges
Overcast	Add 2 stops to f/16: f/8	Barely visible
Heavy overcast	Add 3 stops to f/16: f/5.6	Absent
Open shade	Add 4 stops to f/16: f/4	Absent
Backlighting	Add 1 stop to f/16: f/11	-

For more a more complex method to determine exposure, see Light & Exposure Values.