What Is the Sunny 16 Rule in Photography?

Download Article

Snap the perfect shot with this easy trick

Co-authored by Crystal Bear and Eric McClure

Last Updated: September 2, 2026 Fact Checked

Download Article

The Sunny 16 Rule Explained

|

Using the Sunny 16 Rule

|

Looney 11 Rule

|

Expert Tips

|

FAQ

|

Video

The sunny 16 rule is a simple and easy-to-memorize photography trick that you can use to determine what aperture and shutter speed you should use based on the amount of light around. It's a good rule of thumb if you don't have access to a light meter. In this article, we’ll explain how you can use this rule to improve your skills. We also spoke to professional photographers to get extra tips for using a film camera.

Sunny 16 Rule Chart

Download Image

A diagram displaying the different manual camera settings based on the Sunny 16 rule.

The sunny 16 rule is a photography trick that helps you identify the best aperture and shutter speed settings for your film’s ISO based on the amount of daylight there is. For full, normal sunlight, you start at f/16 and the same shutter speed as your film’s ISO (so 1/200 for ISO 200).

Section 1 of 4:

What is the sunny 16 rule?

Download Article

The sunny 16 rule is a guideline for exposure settings in daylight. If you’re shooting on film and you do not have access to a light meter, the sunny 16 rule is a simple guideline for choosing what kind of exposure settings you should use to shoot. The rule is basically summarized as this: On a normal, sunny day, set the aperture to f/16 and the shutter speed to the same setting as your film’s ISO. Here’s an example of how this works on a practical level:^{[1]
X
Research source}
- You have your film camera but no light meter. It’s a typical sunny day around noon. You have ISO 400 film. You’d set the aperture (f-stop) to f/16, and since you have ISO 400 film, you’d set the shutter speed to 1/400.
- If your camera had ISO 200 film, you’d set the shutter speed to 1/200 instead.
- It’s okay if your camera doesn’t have the exact same shutter speed setting as the film’s ISO. Just use the closest setting that is above the number you’re supposed to be at.
- FYI, you can download a light meter app for your phone if you don’t have access to a light meter and you actively want one.
Meet the wikiHow Experts

Vlad Horol is a professional photographer and the co-founder of Yofi Photography, a portrait photography studio based in Chicago, Illinois.

Crystal Bear is a professional photographer and the owner of Summer Bear Photography. She has expertise in lighting and lighting-related settings.

Corey Reese is a photographer with over 18 years of experience shooting in a variety of different settings.

Section 2 of 4:

Making Adjustments with the Sunny 16 Rule

Download Article

Move down one f/stop and shutter speed notch per layer of cloudiness. Every photographer knows that the sun isn’t always going to cooperate with a great shot, so which setting do you use then? Luckily, the sunny 16 rule is designed to make adjustments easy. To put it simply, you move down one notch on the aperture, and up one notch on the shutter speed for each additional layer of cloudiness. Here’s a simple chart that should make it clear how this works in practice:^{[2]
X
Research source}

Sunny 16 Rule Settings
Daylight Level	Aperture	Shutter Speed	Stop Difference
Normal Daylight	f/16	1/200 (with ISO 200 film)	0
Cloudy	f/11	1/400 (with ISO 200 film)	-1
Overcast	f/8	1/800 (with ISO 200 film)	-2
Darkly Overcast	f/5.6	1/1600 (with ISO 200 film)	-3
Twilight	f/4	1/3200 (with ISO 200 film)	-4
Sunset	f/2.8	1/6400 (with ISO 200 film)	-5

Note: If your film is, say, ISO 800, you’d start at the top (under daylight) with 1/800 shutter speed. Then, you’d move one stop for each layer of cloud cover. So, it’d go 1/800, then 1/1600, etc.

Section 3 of 4:

What is the Looney 11 rule?

Download Article

If you’re into space photography, you may come across the Looney 11 rule, which is basically the same thing as the sunny 16 rule but with slightly different numbers. Instead of starting with f/16, you start with an aperture of f/11. You set the shutter speed to the same level as the ISO. You move by one notch (both shutter speed and aperture) based on how much more exposure you want.^{[3]
X
Research source}

Section 4 of 4:

Expert Advice on Using a Film Camera

Download Article

You can totally go higher if you have to, but professional photographer Vlad Horol doesn’t recommend it. “I'll always start at ISO between ISO 100 and 400, generally around 400. And then I'll move my shutter speed to adjust the light.” In other words, if you’re going to mess with your camera’s settings and you’re worried about the fidelity of the image, adjust the shutter speed before you swap out the film to a higher ISO.^{[4]
X
Expert Source

Vlad Horol
Professional Photographer

Expert Interview}
2
Buy a light meter if you don’t want to master the manual settings yourself. Some film purists hate light meters and think that it’s sort of like cheating yourself out of a photography education, but if you just want perfect images, get a light meter. Professional photographer Crystal Bear explains: “It's an external device that you can actually place on somebody's forehead or wherever you want to take the photo, and it reads the light where that person is... You tell the light meter ‘Hey, I'm at 400 ISO. What does my shutter and aperture need to be?’ So, it's just an easy way to tell the camera exactly what it needs to be set at.”^{[5]
X
Expert Source

Crystal Bear
Professional Photographer

Expert Interview}
- Bear recommends using a dedicated light meter if you’re shooting on a digital camera, too! She says the built-in sensors aren’t “100% accurate” the way a dedicated light meter will be.^{[6]
  X
  Expert Source
  
  Crystal Bear
  Professional Photographer
  
  Expert Interview}
You (and most people out there) are going to be used to just pulling your phone out and snapping photos quickly, but it pays to be patient with a film camera. Photographer Corey Reese says that with film, you have a limited number of shots, so it pays to sit and think about the specific settings you’re using before you shoot a photo. Really take a second to look at what you’re shooting and think about each setting individually before doing anything.^{[7]
X
Expert Source

Corey Reese
Photographer

Expert Interview}

Common Questions: Understanding the Sunny 16 Rule

Does the sunny 16 rule apply to digital mirrorless cameras? Yes, although you shouldn’t need to use the sunny 16 rule if you’re using a digital camera. The purpose of the sunny 16 rule is to give you a rough sense of which exposure settings you should use when you don’t have access to a light meter. Since every digital camera has a built-in light meter, you don’t need to do any guessing.^{[8]
X
Research source}

How does exposure latitude affect the sunny 16 rule? Exposure latitude is the whole reason that the sunny 16 rule works in the first place. Exposure latitude—the acceptable range of exposure for an image to be clearly captured—means that you don’t have to have the perfect exposure settings to achieve a visible, high-quality result. Sunny 16 is a ruleset that gives you a general set of guidelines for exposure settings, which works so well because exposures don’t have to be perfect!^{[9]
X
Research source}

How do you calculate shutter speed and ISO with the sunny 16 rule? It’s a qualitative process, so it starts with you doing your best to determine just how bright the light outside is. Just ask yourself, “Is this a normal, clear sky, cloudy, overcast, or sunset?” From there, the rest is easy. You start at f/16, choose the same shutter speed as your film’s ISO, and then you move one notch for the shutter speed and aperture based on each step you’re removed from normal daylight.^{[10]
X
Research source}

What ISO should I use with sunny 16? The ISO itself doesn’t matter; you adjust the shutter speed to compensate for it. So, if you have ISO 800 film, you turn the shutter speed to 1/800. If you have ISO 400 film, you turn the shutter speed to 1/400.^{[11]
X
Research source} If you’re wondering what the ideal ISO for normal sunlight is, you’ll get the best results with ISO 100-200 film.

Is the sunny 16 rule accurate? Yes, most photographers agree that it’s a relatively accurate and helpful rule of thumb. It’s not going to be the best way to determine how to get the perfect settings (you need a light meter for that), but it’s going to be a lot better than simply guessing or going on vibes if you don’t have any intuitive sense for which settings to use.^{[12]
X
Research source}