How To: Use Metering for the Correct Situation
The camera’s light meter reads the light reflecting off the scene and entering the lens. The camera then decides what exposure values to set for the scene based on how it is metered.
If the light levels in the scene are low, the camera will try to set the exposure to make the scene appear brighter and vice versa when the scene is too bright.
This may produce good results in most cases. However, by controlling how the camera sets the exposure based on the meter reading, you will be able to control how the scene is finally rendered. In difficult lighting, you need to know how the meter will react and what controls are available to you to get the best possible result.
The camera divides the frame into zones, takes light information from each zone and calculates a reading based on the combination of these zones. If you have a scene with low contrast areas, this metering mode will work best.
In this metering mode, the camera takes a reading from only a very small part of the image, usually the centre of the scene. This metering mode works well when you have high contrast and backlit scenes.
Here, the camera takes a reading from the entire scene first and then the centre of the frame. It makes its final calculation with extra weightage given to the reading from the centre.
This article originally appeared in the May 2014 issue of Better Photography.Tags: centre-weighted metering, evaluative metering, metering, spot metering