52 Photo Tips #8 – Learn the Sunny 16 rule

Spare a thought for the film photographers from decades past, learning their way without all the helping hands we take for granted today. Few cameras – except the most expensive – had any kind of meter built in. Photographers, if they had the money, had to make do with handheld meters (if they could afford one) or guess the exposure.

This was easier said than done considering many cheaper cameras had only a few speeds and apertures. Photography with the likes of a Kodak Brownie or an Agfa Clack could feel like guesswork. But there as a simple trick for taking perfectly exposed pics. And it’s something that still works a treat today.

The Sunny 16 rule might be the simplest piece of technical advice you can learn in photography. What’s more, it’s pretty much foolproof.

Sunny 16 is a mathematical equation that allows you to expose properly in outdoor lightning conditions. The rule means that for bright sunny weather – the kind you’re likely to find on your summer holidays, when most people were taking photographs – you set the aperture to f16 and the shutter speed as close to the ISO of the film you are shooting with; if you have 100 speed film, set the camera’s speed to the 1/125th. If your film is ISO 200, set the shutter speed to 1/250th. “Sunny weather” means bright sunshine with clear and distinct shadows.

The Sunny 16 rule doesn’t end there; the right exposure for other lighting conditions can also be worked out – right down to overcast days. The table below gives a good indication.


Deep shadows
Hazy Sun
Soft Shadows
Faint shadows
No shadows
F-Stop/ 16/ 11/ 8/ 5.6
ISO 1001/1251/1251/1251/125
ISO 2001/2501/2501/2501/250
ISO 4001/5001/5001/5001/500
ISO 8001/10001/10001/10001/1000

The Sunny 16 rule might seem archaic given that, with a few clicks, a light meter app can be downloaded for your smartphone. But learning it allows you to understand light, and confidently expose for the conditions. And getting the exposure right is often half the battle.

In bright sunshine, where your subject isn’t hidden in shade, the Sunny 16 rule will stand you in pretty good stead.

But it’s also a brilliant tool for shooting on overcast days. Living in London, I see a lot more of those than I do sizzlingly sunny ones.


Because Sunny 16 is a basic mathematical rule, it is predictable – and flexible. The above shot was taken on 400 ISO film rated at 3200; that means it’s pushed three stops and needs either a shutter speed three times faster, or an aperture stopped down three extra stops…. I double-checked with a handheld meter, but my basic calculation was pretty much on the money. Sunny 16, it turns out, is Cloudy 16 too!



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