All camera’s have exposure metering modes. Each metering mode determines which part of the frame should be analyzed to determine a good exposure. Here I will list the basic terms and what each metering mode is.
- Evaluative metering: The camera analyzes the entire frame and then selects exposure settings designed to produce a balanced exposure.
- Partial metering: The camera bases exposure only on the light that falls in the center 9 or so percent of the frame.
- Spot metering: This mode works like Partial metering but uses a smaller region of the frame to calculate exposure. For Spot metering, exposure is based on just the center 4 percent of the frame.
- Center-Weighted Average metering: The camera bases exposure on the entire frame but puts extra emphasis, or weight, on the center.
I personally use partial metering 90% of the time. I just find it gives me a nice consistent exposure for my taste. On the odd occasion I use spot metering where the scene is very contrasty, such as when there is a lot of bright and dark area’s. Spot metering is also very useful when your subject has backlighting and you need to get a great exposure of the subject.
The image above was taken at a mine dump, with the sun behind my model, and I wanted to get a blown out background, some rim light on her body and hair. Here I used spot metering to meter for the model, to make sure the background was very light and the exposure on my model was good to slightly over exposed.