What is The Sunny 16 Rule and how can it help you learn manual exposure!
 Actor Nick Slie as the Loup Garou...seen in the Swamps of Pierre Part!!! ©Zack Smith Photography

Actor Nick Slie as the Loup Garou…seen in the Swamps of Pierre Part!!! ©Zack Smith Photography



Welcome to the first edition of Zack Smith Photography’s “How to Tuesdays” where I will teach you some of the most common, and slightly random, techniques and share helpful insight and tips on photography’s most interesting and fun topics. Have a question or topic involving portrait and commercial photography, editing workflow and more you’d like to see covered in the next “How To” Tuesdays? Be sure to comment below with your question or topic, or email me at zack@zacksmith.com and I’ll answer your questions right here In an upcoming post. The Sunny 16 Rule is a great way to determine the proper exposure settings for your shot. However, explaining the Sunny 16 Rule will require some background information on your camera:


Exposure settings are decided by the aperture, ISO, and shutter speed. When these settings are correct, a photographer can expect to take the best shot of his or her subject. So here is some information on each one:

The aperture is simply a hole within the camera’s lens. Through that hole, light travels into the camera body. The larger the hole is, the more light can pass through to reach the camera’s sensor. The aperture also controls the depth of field, which is the part of a shot that appears to be sharp. When the aperture is small, the depth of field is large, and when the aperture is large, the depth of field is small. The aperture is normally expressed in the photography world with an F followed by a number. This is known as the focal ratio. The number following the F is the ratio of the diameter of the lens aperture to the length of the lens.

The ISO is the level of sensitivity your camera has to the available light. A lower number represents a lower sensitivity to light, while higher numbers equal more sensitivity. Grain and noise in images increase as the ISO increases. These settings will need to change based on your scene. When you are outside, your setting will be a lot different than it is when you are shooting darker indoor scenes.

Lastly, the shutter speed is the amount of time that passes between a camera’s shutter opening and closing. It basically determines how long the light gets to the camera’s senor. Shutter speeds are normally measured with fractions of a speed less than one second. Fast speeds help freeze motion and are typically great for sporting events and other action shots. Slower speeds allow more light into the camera’s sensor and are great for posed photos in darker environments.


Thanks to the development brought on by the rise of digital camera technology, cameras now have their own light meter. The light meter is built in to most cameras. The meter reacts to how intense the light in the shoot location is as read by the camera. The meter collects the light, which is passed through the camera’s lens and measures the intensity of that light.

Light meters put you in the right neighborhood for how your aperture, ISO, and shutter speed should be set. So basically, the light meter is a God-send for people who are looking to make sure their photo isn’t too over- or under-exposed.

But the light meter does have its downsides.


Obviously, the light meter can be a useful tool in deciding the correct camera settings to shoot with. But the meter comes with some downsides. One downside comes with rooms or outdoor scenes with extreme light contrasts. For example, there may be a very shady area on a sunny day that throws off the meter, or a dark or very light corner of a room. In more recent years, some cameras have been built with additional light meters that can spot read different areas of a photo to address this problem.


Anyone who owns a camera that was created in the last few years will have a light meter in built into their camera. However, many photographers seldom use the light meters nowadays.

Although cameras have evolved so much so that photographers can purchase cameras with anywhere between one and 12 built-in light meters, photographers rarely actually use the light meter to find the correct exposure settings for their environment. This is because the photographer can just take a photo and review your image quickly to know what settings need to be changed. If you are overexposed, you know you can stop down, and if you are underexposed, you know you can open up. If things look right, you can start shooting. So, the light meter isn’t typically used in today’s digital age.


What if there was a way to have a starting point in deciding what settings you need for the perfect exposure? That is where the Sunny 16 Rule comes into play. The Sunny 16 Rule is a way to meter for correct exposure in daylight scenes without using the camera’s meter or simply guessing the right aperture, ISO, and shutter speed settings.

Back when many photographers used their light meters, a photographer would be in a lot of trouble if his batteries ran out. Say the photographer is using on his meter to read light out in the swamps of Louisiana while photographing the elusive Loup Garou (werewolf), he wouldn’t be able to meter and read the scene, meaning he could miss his once-in-a-lifetime shot. The Sunny 16 Rule is the perfect way to assure you will get the shot you’re looking for without having to toy with the light meter and settings excessively.

So here is the rule: The rule states that, to properly expose for the highlights of a subject directly lit by the sun, your exposure should be set specifically so that your aperture is set to F16, and your shutter speed is 1/ISO.


To put it in simpler terms, that means if you set your aperture at F16, and your shutter speed is at 1/ISO (if you’re using 400 ISO, then your shutter speed is 1/400), you can take a test shot and the subject illuminated by the sun will be perfectly exposed. So, for that photographer in the swamps of Louisiana, the Loup Garou, which is illuminated by the sun, will be perfectly exposed.


But why is the Sunny 16 Rule so much more convenient than using the light meter? Let’s take our Loup Garou into account for a moment. If he is hard to catch on camera, you will need to be ready and able to photograph him whenever he comes into the shot. If you are using the camera’s light meter, you must take time to use the meter to survey the light and set your camera. However, if you use the Sunny 16 Rule in your outdoor scene, all you have to do is take a test shot. If you feel you have to adjust the settings a bit after taking your test shot, you can.


If more light is needed, open up. You can open up either your aperture one stop to F11 (3 clicks to the LEFT) or your shutter speed to 1/200 (same!) will give you more light all over, but make sure the change works well with your aesthetic (more on that soon!).

If it is cloudy outside, change your aperture one stop to F8, or even F5.6 at 1/ISO. You can always review your shot to see what the image will look like. Make sure not to open up more than your depth of field. Remember that your depth of field determines what part of the image is in focus. If you have your aperture all the way open, your image won’t be very sharp. Choose the setting that will allow you to get all of the Loup Garou in focus.


In conclusion, using the Sunny 16 Rule is a great way to get a start in deciding what your exposure settings need to be in any day-lit scene. It is typically a much easier and faster way to get your camera photoshoot ready!

That’s it for this week’s “How To” Tuesday. Next up:

“How To” Tuesdays #2 – Let your subject set the settings: How to navigate the many settings on your camera to get the perfect composition and exposure!


Zack smith is a fine art and commercial portrait photographer who has documented the social, musical and cultural landscapes of Louisiana for the past 15 years. As a musician, artist, and storyteller, Smith believes the world gets smaller as we celebrate our similarities and connect through our traditions and stories.

Smith’s work has appeared in numerous ad campaigns, and he has done work for The Louisiana Public Health Institute, New Orleans Tourism and Marketing Commission, Getty Mages, NIKE, Russell Simmons, YAMAHA, St. Charles Vision, Krewe du Optic, Dirty Coast, and SOPO among others.





The Sunny 16 rule is a GREAT way to get a starting exposure in any day lit scene!

FOLLOW this BLOG and stay in touch for next week’s “HOW TO TUESDAY’s”

#2 – LET THE SUBJECT SET THE SETTINGS!!! – how to navigate the many settings on your camera to get the perfect composition and exposure!


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