If you have been taking photos for a while, you may have noticed a curious phenomenon: when you take photos in very bright conditions, like at the snow, they turn out too dark, and when you take photos in dark conditions, they turn out too light. So why does this happen?
Well, first of all it is important to note that because a lot of the time cameras reproduce more or less what we see with our eyes, it is easy to fall into the trap of thinking that we can just put the camera in fully automatic mode, point, shoot, and get a photo that looks just like what we saw. But this is not always possible, and it is because of the way your camera makes decisions when you press the button.
Unless you are using a fully manual camera, your camera must make the decision as to how much light to allow the sensor to be exposed to. If there is too little light, the subjects of the photograph may appear almost invisible, also known as ‘underexposed.” In reverse, if there is too much light allowed, areas of the photo may be completely white, also known as “overexposed.”
Basically, your camera makes this decision based on the fact that most scenes, most of the time, are a mixture of light and dark tones that average out about the same. This average is called 18% grey. It uses this rule of thumb to work out what combination of shutter speed and aperture to use. However, this breaks down in some situations.
Consider for example what happens if you take a photo in very bright conditions, perhaps the classic example of a polar bear at the snow on a sunny day. You will want your photo to come out very bright, reproducing what you saw with your eyes. However, it is very likely that the photo will instead render the bear and snow as a kind of dirty grey. That’s because your camera is applying its rule of thumb to a situation that is unusual.
The other situation is when you take a photo in dark conditions, perhaps a street at night lit by some streetlamps. Here you want most of the photo to be dark, with perhaps some lighter areas that were illuminated by the streetlights. Instead what you may get is dark areas that are dull brown rather than black, and lighter areas that are overexposed. Again, your camera has assumed this scene, like others, is 18% grey, and has exposed it accordingly.
To manage these situations, you will need to take over control of your camera. This means the camera will no longer be able to make its own decisions. One way to achieve this is to dial the ‘exposure compensation’ setting on your camera. A good rule of thumb to go by would be one stop forward for bright scenes and one dial back for darker scenes. An additional option is to turn your camera into manual mode. This will allow you room to play and experiment with settings as you view them in your LCD screen until you determine the exposure you are looking for.
Tobias Sterling is a keen photography enthusiast and featured writer on Clivir.com. His articles about Beginners Photography Basics and Female Body Sensual Photography can be found on Clivir.com.