Sunny 16 Rule (Manual Mode)
On a perfectly sunny day when shooting outdoors, set Aperture f/16. The sunny 16 rule is obviously more useful when shooting landscapes, as it presumes you are wanting a wide depth of field and no background blur.
If you set ISO 100, use a Shutter Speed of 1/100 sec
If you set ISO 200, use Shutter Speed 1/200sec
If you set ISO 400, use Shutter Speed 1/400sec
If you set ISO 800, use Shutter Speed 1/800sec
What if you don’t want to use aperture f/16? Every time you decrease your aperture number, also increase your shutter speed by the same number.
Exposure rules from film photography days that still work today!
Slightly Overcast F/ll Rule – If the weather is mostly sunny with some cloud cover and you’re shooting outdoors, set aperture F/ll and use the same ISO to Shutter Speed combinations listed above.
Overcast F/8 Rule – If the weather is overcast and you’re shooting outdoors set aperture F/8 and use the same ISO to Shutter Speed combinations listed above.
Remember you need to choose the ISO / Shutter Speed combination that matches the subject you are photographing. For example if you are photographing your child’s baseball game, you may want to keep the Shutter Speed to 1/800sec for sharp shots. If you are photographing a landscape scenery, you’ll most likely choose a slower shutter speed of 1/l00sec.
Heavily Overcast F/5.6 Rule – Set aperture F/5.6 and use the same ISO to Shutter Speed combinations listed above.
Sunset F/4 Rule – Useful for photographing subjects against a setting sun. Use aperture F/4 and use the same ISO to Shutter Speed combinations listed above.
The F/4 rule is perfect for portrait photography at sunset.
If you are hand holding your camera, remember to choose a combination that is faster than the length of your lens. For example, if you use a 70mm focal length, choose ISO 100 and Shutter Speed 1/l00sec combination. If you are using 200mm focal length, choose the ISO 400 and 1/400sec combination to avoid camera shake.
How to use the sunny 16 rule to test your camera’s exposure
Have you ever thought your camera consistently under or over exposes one shot after another? It seems you may not be imagining it. Canon cameras in particular are known to underexpose shots by 1/3rd. Some photographers like it, others don’t.
A good way to check if your camera is spot on with exposure is to use the sunny 16 rule. The idea with the Sunny 16 rule is that on a perfectly sunny outdoor day, the following settings will result in a sharp image that is neither under or over exposed.
Aperture f/16, 1/l00th of a second Shutter Speed and ISO 100.
Take several shots with the settings above and look at the results on your monitor. If they seem too under or over exposed for your liking, then adjust your camera’s default exposure compensation to suit. I know many photographers who keep their exposure compensation on +1/3rd for this very reason.
Another way to test your cameras exposure is with the use of a gray card. Lay the gray card down in fuII sun and zoom your lens in to fill the frame with the card. Set your camera to manual mode and use the settings listed above. If your exposure line automatically zeros, then you know the camera meter is spot on. If not, you may like to adjust your default exposure compensation accordingly.