Tuesday, January 30, 2007
The Magic Of Histograms
Learn to read your camera's histograms and get the best exposures possible for your subject
Labels: Learning Center
Some low-contrast scenes should be kept low contrast, such as foggy skies. Other scenes need correction, however. This is a good scenario for RAW capture, since it will allow stretching of tones without damage to the image. On many cameras, you can choose different contrast settings for the conditions, for example, setting a custom parameter on your camera just for cloudy days that increases contrast and saturation.
Overall, you want your photo to display a histogram that slopes down as close as possible to the most important brightness values of your photograph. If the highlights are critical, then the slope must end at or before the right side. If the shadows are essential, then the slope must favor the left side. This can be decisive in getting an image with proper data going into your computer.
There are several ways of making these adjustments. The easiest way to deal with a scene is to become very familiar with your camera's Â± exposure compensation control. Dial it down (minus, for less exposure) when the histogram is bumping the right side of its area; dial it up (plus, for more exposure) when the histogram is too far to the left.
There are no absolute rules for using a histogram. Every scene is different. You'll need to interpret the histogram as it relates to the scene in front of you and what you believe is a good way of seeing the scene. It's worth experimenting, since there's no cost to taking extra shots in digital. Try different exposures and see what they look like on the histogram to learn how this function reads various scenes.
Page 4 of 4