An online book of Common Sense Photography, by Rhett Stuart

Tips on Getting a Good Exposure

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Pick out the dark area of your photographs, the light areas, and the medium areas. Medium areas are referred to as middle gray. Think about how you would like to have each of these areas show up in the photograph. Make the best judgment call you can and take the picture. Carefully analyze your photograph to see how you liked the exposure. Getting the exposure right improves with more experience. Consider taking a few extra pictures that are over and under exposed in case they turn out better then what you had guessed at. Some cameras can be set for this automatically, it is called bracketing.

Decide what you want properly exposed and either get closer and get an exposure reading with your built in camera meter, or use the built in spot meter in your camera (if it has one) to determine what exposure setting you should use. Most cameras have “exposure lock” to hold this setting while we compose the picture. The exposure meter will measure more light as you get closer so it is advisable to overexpose by one f/stop over your exposure reading to properly expose a shadowed face. Also, reflective light will affect the spot meter in bright areas so either way, over expose by one f/stop is usually a safe thing to do.

For example, you are 20 feet away and want to get your friends faces properly exposed but there is a lot of bright sand and ocean around. Use the spot meter on the darker of your friend’s faces to properly expose it, or get closer and use the center weighted light meter on just their face (see your camera manual!). Notice the aperture setting, and ISO setting. Now manually “lock” the exposure, or manually set the exposure for what the reading was, but make the aperture is one stop bigger, or the shutter speed one stop slower, or the ISO the next highest speed.

Using the automatic metering on your camera without your brain will work a lot of the time. The camera tries to make everything medium grey. By thinking and selecting what I want properly exposed, I sometimes overexpose the automatic expose setting by 1/3 to 2 f stops. My Canon has a round dial in the back with a switch to turn on the under/over exposure. I can quickly rotate the dial with my thumb and take a few extra pictures overexposing the picture by say 2/3, 1, and 1 1/3 f stops to get the right effect. I usually use the overexposure more then underexposure since I am trying to bring out faces in bright back lit conditions, or reveal details in shadows. Underexposing will bring out details in bright objects and won’t wash out the details. Overexposing will reveal details in the shadows and dark areas of the photographs, and correctly show white objects that take up most of the camera frame (like snow and white beaches) as white, and reveal details in darker objects (like faces). Over exposing will also show white buildings and snow as white. The automatic exposure in a camera will try and turn everything medium grey unless I do something about it!

Snow is difficult to photograph correctly. The camera metering will try and turn the snow grey looking. I suggest 2 f stops, and if you want some texture in the snow, like when snow is lit from the side, use about 1 1/3 f stops. For white sandy beaches over expose your photographs by 2 stops from what the camera exposure reading is normally so all the people don’t wind up dark. The sand will look more naturally white, and the faces will be brighter. SLR cameras have a setting to automatically overexpose each photograph by 1-2 stops. Remember to turn off this feature when you leave the beach so your other pictures aren’t overexposed later!


Sometimes it is impossible to expose everything correctly. For example, the interior of a room is dark, and the bright outdoors can be seen through the windows. The camera will just expose the photograph for the bright outdoors, or the inside. It can’t see everything as well as your eye. Photoshop® to the rescue! Put the camera on a tripod, and take 3 pictures. Take one exposure for the bright window area, one for the dark interior room, and one exposure in the middle. Later, on the computer, edit the images and combine them so everything is exposed correctly!

This can also be done for sunsets with a good tripod. Take an exposure while it is still light; wait for the sunset, and take another photograph of the sunset while the camera is in the same position on a tripod. Cut the sunset off at the horizon and “paste” it in Photoshop® with the foreground layer of the photograph you took when the sun was still up.

Proper exposure is the right mix of the Depth of Field, shutter speed, aperture setting, and ISO speed. Sometimes you can’t have both a fast shutter speed and a small aperture since there isn’t enough light, so a faster ISO is needed. Good photographs are sometimes a compromise between all these settings.

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