This is a tool that is overlooked by many photographers. It has a huge impact on your images and can make all the difference to your picture’s end result.
When taking a light reading, you are in fact reading the amount of light that is available around you through the cameras lens. The metering mode gives the camera more information as you are now refining how the camera reads that light and the more control you have over the light the better your images will be.
Different metering modes are used for different situations and should be used accordingly. Obviously rules are meant to be broken but you must learn the rules first. Next time you are taking pictures, select the different metering modes and you will see how different the results of each image are. Changing the metering mode has a huge impact on your images.
So where do you find the metering options? On the camera you usually have several different places where you can find the same thing; on the back of the camera and in the main menu system are the most common. The logo for the metering options looks like the rectangle shape with what looks like an eye in the middle.
There are 4 different types of metering options; centre-weighted, spot, partial and evaluative. Each one reads light in a different way resulting in specific exposures.
1. Centre-weighted average metering
The light is measured across the whole lens but takes most of the reading from the centre point. Itdoes not take the focus into account and uses the same average reading for every shot. Most of the time I use this for landscape photography.
2. Spot metering
Spot metering measures the light in the middle of the lens; a very small circular area covering just 2%-4% of the picture area. This gives you a very precise light reading and can be used for small subjects or areas of interest. It can also be used when light is behind a subject, which results in the light falling on to the subject rather than the light from behind the subject which would ordinarily give you a silhouette.
3. Partial metering
Partial metering is a little larger that spot metering, and reads about 8%-13% of the lens. Again this can be used for things like group shots or portraits when the light is behind them.
4. Evaluative metering
This is the default metering mode and can be thought of as auto. Light is measured across the whole of the lens but is very biased to the focus point being used.