by David Tong

Figure 1: A Pretty Average Scene

After writing my previous articles discussing exposure (here and here), I received a couple of emails asking me "what is metering and how do I use it?", and it made me realize that while the concept is simple, it's not as easy to understand with all the jargon that goes with explaining what metering is.

Virtually all 35mm cameras that were sold after 1980's have built-in meters. The built-in meter helps the user and/or the camera's sensor to determine what exposure settings (shutter speed and aperture) the camera should use to obtain a "proper" exposure. As mentioned in my previous article, the camera's meter can be pretty accurate for "average" scenes where the bright, middle, and dark shades of the scene are pretty well distributed, like the image above.

The image has bright areas (clouds, sky, and the light building), a lot of midtone (the front building, the road, the trees), and ample dark areas (the areas under the elevated highway). That is a pretty average scene, and most of our photos do fall under such lighting conditions, which makes sense to rely on automatic metering. Continue Reading