Sunny 16 Rule

The Sunny 16 Rule is a method of setting exposure for photography that is based on the illumination that is provided by the sun as a light source. This ignores any individual reflective properties of subjects you are photographing, a favorable point for choosing this type of exposure method. Your camera's reflective light meter reading differs from the Sunny Sixteen because it is entirely dependent on the reflective light it reads from objects.

The Sunny 16 rule gives an excellent exposure that holds good highlight details and allows subjects to be photographed revealing their natural reflective tonal values. It works with any ISO rating film or light sensitive medium you happen to be using because ASA and ISO numbering systems were base on this light constant.

It does require you to shoot with the sun about +35º above the horizon, no haze present, and clouds can't be obscuring the sun light, it is best to have the sun behind you or over one shoulder so that the sunlight is lighting the same direction your are photographing. Looking towards the sun, and into the shadows is not going to work so well.

For instance, what exposure would you use if it were bright but hazy out and not clear, or if it were cloudy, or even stormy dark weather, or open shade. These would all be different exposures. Without a light meter to use, you would use one of the approximate exposure suggestions of BDE correction from which to set exposure by. The thicker the cloud cover gets, the harder it is for you to guess correctly what exposure you should use. The hand held incident light meter was the great equalizer to this problem.

Randy Smith Photography © 2011. - Sunny 16 Rule

This exposure is BDE +2/3 stop. The reason for the over exposure correction is because the Sunny 16 Rule requires the sun's light to be above 35° above the horizon depending on the amount of atmospheric haze the light has to travel through. We don't see much sun in Alaska in winter and it is often low on the horizon. The sun in this picture is maybe about 25°, so I needed to open up the exposure a little.

Since you have a Digital Camera and can also set exposure manually, you might try your hand at setting exposure for outdoor scenes using this method. It might give an appreciation for how the photographers of the past had to develop a technical and intuitive sense about their photographic skills.

Light meters freed us up to get an exposure reference so we could take pictures under any kind of lighting, indoors or outdoors, day or night. Most hand held light meters are called incident light meters, they are reflective light meters that have a little white plastic dome that slides over the light sensitive photocell, this allows for an incident meter reading to be taken.

The incident reading requires you to point the sensor towards the light source that illuminates the scene. The reflective light meter reading requires you to point the light meter towards your subject without using the dome over the sensor, and the meter reads the light being reflected off of your scene. The reflective light meter is fooled because it does not know what reflective properties your subjects really have.

The Sunny Sixteen Rule is an Incident reading by principle. The brightness of the sun has been measured by an incident meter reading already, we don't have to measure the sun light again, the sun light is a constant, we just have remember the rule. The nice thing about incident light readings is that subjects in our scene don't strongly influence the exposure reading itself to any great degree, we are just getting an exposure that is based on the light that illuminates the scene. See : Photography Light Meter.

Along with the advantages that came with manufactures placing reflective light meters in camera's came the disadvantage of your having to interpret the reflective nature of your subjects. People get poor exposures using reflective light meters when they don't consider the natural reflective quality of the subjects that they are photographing. Most of the time, we should capture light toned subjects as objects that are light in tone. Dark objects should be dark objects. We consider how to manage this issue on the link Understanding Exposure (see link at bottom of page).

There is no reason you can't use the Sunny Sixteen Rule in this day and age. If you are photographing a bright white sea gull on a black lava beach, or black raven on the snow, these are really the same exposure, provided it's a clear day and sunlight is illuminating the scene.

However, it may take a bit of practice for you to make judgements accurately of exposure on Hazy, cloudy, stormy, or open shade type lighting scenarios as there are variant atmospheric conditions. You may find that you also like your exposures a little lighter than the Sunny 16 rule, becareful you do not overexpose those highlights though. With any exposure method, it takes a little practice to use to. However it is a useful tool and exercise. Try it, it's fun, and you learn more about exposure.