Photography 101 – Exposure Compensation
Written by: Tiffany Joyce
The exposure compensation feature on today’s digital cameras does what the name suggests – compensates the exposure of the shot according to the conditions in which the photo is being taken. Exposure compensation is used to manually adjust the exposure to something different than what the camera’s meter is suggesting. The photographer can tell the camera to allow more light in (positive exposure compensation) or to allow less light in (negative exposure compensation).
Most digital SLR’s offer exposure compensation of up to plus or minus two stops, in 1/2 or 1/3-stop increments. This feature can be used whenever your camera is on any non-auto mode (P (for program), S (Nikon shutter priority), TV (Canon shutter priority), A or AV (aperture priority) and M (fully manual)). When shooting in Manual Mode, the camera will adjust the aperture and shutter speed to achieve the level of exposure compensation desired. When shooting in S/Tv mode, the camera achieves the desired exposure compensation by automatically adjusting the aperture. When shooting in A/AV, exposure compensation is achieved by adjusting the shutter speed. (Generally speaking – your camera’s process may vary.)
Exposure compensation comes in handy in circumstances when your camera’s sensors or light meter can be “fooled” by the quality of light that it detects. A beach scene with a wide body of water, or a snowscape, or other scene where there is a lot of reflected light, are some examples of conditions that might fool your camera. The end result is that some parts are over-exposed, some parts are under-exposed, and the main subject is incorrectly exposed. On the other end of the spectrum, if the surroundings are too dark, the camera compensates for it by over-exposing the subject.
On both Nikon and Canon D-SLR cameras, the exposure compensation button looks like a plus and minus sign (+/-), and is located either near the shutter button, or near the LCD screen on the back of the camera. The button is used in tandem with the control wheel or dial – hold down the button and turn the wheel to the left or right to incrementally adjust the exposure compensation. This is also known as “stopping down” or “stopping up”, where one increment is known as a “stop”.
Take a practice shot and consider its quality. Recompose the shot and auto-focus it (press the shutter button half-way), then adjust the exposure positively or negatively. Take the shot again, and if it still isn’t quite right keep messing with the exposure compensation until you’re happy with it.
For a great example, check out this tutorial by Kevin Cole on Flickr.
Photo Credit: “Long exposure self portrait” by Paul Alsop on Flickr Creative Commons.
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