Any DSLR camera worth its salt will have at least four distinct light metering modes of reflected light. By reflected light, I mean the light that is reflected by the subject you are photographing.
Back in the 1920, George Eastman, the founder of The Eastman Kodak Company, came up with a cumbersome and complex system for measuring light. After shooting thousands of photographs, he came up with a unique metering system that is still used after all these years.
His light metering system consists of the following modes:
- Evaluative Mode also known as Matrix Mode, Honeycomb Mode or Zone Mode. It consists in dividing a scene into zones and then averaging them to come up with well exposed photographs. It can improve your chances of getting a good exposure when you need to grab a shot quickly.Most of the time it works well, but it is affected by the flaw in Kodak’s light metering system which based his light evaluation on the reflection magic number of 18 percent grey. All cameras are set up to capture images based on the assumption that light reflected by objects are 18 percent grey which is not exactly true. Different objects reflect different percentages of light. With black and white backgrounds, the camera meter will never give you a correct exposure based on the average 18 percent grey principle If you are serious about photography, I recommend you to dig deeper into this fascinating subject. Evaluative metering is the only metering mode that’s available in Live View.
- Centered-Weighted Average Mode takes into consideration the different tones of light in the whole image and then averages them up, but providing more importance to the center area of the image. The meter reading is taken across the whole frame. The difference is that it places greater emphasis on subjects in the middle of the image and it doesn’t use exposure compensation—it applies the same average pattern to every shot. It is widely used for general-purpose photographs and large landscapes
- Partial Mode is a light metering system based on the center part of the image . It enables you to take a readings from a very small area in the center of the frame This is small area between 1 to 15 percent of the scene. It is used to take close up images, macro, desktop, or product photography.
- Spot Mode only covers the center AF point and the area immediately surrounding it. It offers a pin-point precision when it coms to metering, although you’ll need to be able to judge tones accurately to get the most from it. It meters anywhere from 2 to 4 percent of the picture area. Spot Metering is mainly used for taking portraits, product photography, desktop photography or colors of the sky.
I was recently experimenting with the Spot Light Metering Mode and the pictures below are the result of practicicing with this mode. Notice how the birds changed their focus by setting your camera to this mode. As they say, “Practice makes perfection.”