Understanding the Basics of Photo Exposure
A picture is an instant in time created by the result of hundreds of tiny details merging together. The length of time that instant lasts can be measured by the exposure of the photograph, and this exposure has an immeasurable impact on the final outcome of the image. Like every good photographer, you'll need to understand how to manipulate the exposure to get the results you want and with a little practice you'll soon understand the theory behind it.
What is Exposure?
Put simply, exposure is the length of time a sensor or piece of film is given to absorb light. A long exposure will result in a washed out bright image, while a short exposure time will give you a dark or muddy looking image. The amount of available light has a major impact on exposure, however in almost any situation it is possible to over or under expose a photograph.
What Does Exposure Do?
Exposure affects a variety of factors in your picture. One of the more obvious affects that exposure controls is how light or dark the image turns out. In dark lighting situations, a longer exposure will be required to allow the camera more time to "see" the subject, whereas in bright lighting situations a fast exposure will prevent the film from being blinded.
Exposure also has an impact on how blurry or sharp moving objects appear in an image. For example if you were to take a picture of a basketball player making a dunk, a fast exposure would give you a clear frozen image of the player making his shot. There's nothing wrong with a little motion blur, but if an exposure is too slow it is likely that high-action shots will turn out unintelligible.
Finally, exposure controls an image's depth of field. Depth of field determines how fast the background loses sharpness and how much of the picture is clearly focused. Short exposures don't give a camera very much time to absorb data, so they will result in shallow depth of field. If you want a greater sense of depth, you can increase the exposure time but your image will have more motion blur.
Working with Exposure
You can control the exposure of any photograph you take by adjusting the shutter speed. Slow shutter speeds give you longer exposure times whereas fast shutter speeds give you very short exposure times. Depending upon what you're trying to accomplish with your image and the type of available lighting will determine if you need to have a long or short exposure. For example, picture you're taking a photo of a kid riding a bike down the street. A long exposure, or lower shutter speed, will give you motion blur as the child rides by, and may also show the houses in the background clearly in focus due to the greater depth of field. A short exposure, or high shutter speed, will freeze the child in frame and will blur out the majority of the background.
In this particular case, a shorter exposure may be your best option if the light is so intense that a low shutter speed will over-expose your image. If you want to adjust your exposure you can reduce the amount of light that enters the lens by adjusting the aperture or f stop on your camera but often times your exposure is dictated by your light source.
Dealing with exposure is just one of the many ways that you can control the final output of your images beyond framing a subject and hitting the shutter button. Once you understand how shutter speed works, you'll be able to easily change the depth and amount of movement in every picture. And fortunately with SLRs these days you can select your shutter speed and the camera will figure out everything else.
About the Author:
Autumn Lockwood is a writer for Your Picture Frames. Shop online and see our selection of flower picture frames in a variety of decorative styles and colors. Visit our website and see our jeweled flower picture frames and lovely yellow picture frames or call us at 1-800-780-0699.