Metering Modes: Be a human meter!

After last night's post, hopefully you know where to find the meter on your D-SLR now. You now need to know how to use it properly. 

Remember, the meter will give you input about the exposure for the ISO, F-Stop, Shutter speed you have set. If the meter shows it's dark (-2 for example), you have to adjust accordingly to allow more “light” into the lens.  A correct exposure will bring the meter to the middle. 

Most cameras, however, have different modes you can use that can give you the info you need to meter various lighting conditions.Here are the standard metering modes found on D-SLR’s (There are a few more advanced and specialized modes but quite frankly I don’t use them often).

•  Evaluative metering (Matrix on a Nikon)
•  Partial metering (Spot on a Nikon)
• Center-Weighted Average Metering  (Center-Weighted Metering on Nikon cameras) 

Evaluative Metering:

The EVALUATIVE mode is the one I use most often. In this mode the reading is taking as an average of the entire scene. In this mode, the emphasis for the meter will be prioritized by the autofocus point. Metering information from that part of the scene is given a little more weight than metering information from elsewhere in the scene. It essentially evaluates the whole frame based on this point and it creates an average for the whole scene. This is the mode from which you'll usually get a good overall exposure. The shot below is an example of it's use.

Taken at College Fjords in Alaska. It was a gray scene with a pretty even light source. Evaluative Metering was sufficient for this scene.. 

Partial Metering:

This setting is most useful when your subject is backlit (think someone with the sun behind).  Basically in this mode, the camera uses information to take a meter reading from a specific part of a scene or subject.  For example, if you are standing on a street looking into a garage with a sports car in it (the garage will obviously be darker) you might want to switch to the spot meter to spot where the car is to determine the exposure.

Below is an image at Yosemite I took using the Partial Meter. 

Use of the spot meter in this image was helpful in determining the proper exposure. The background was much brighter than the rocks and snow in the foreground. 

Center-Weighted Average Metering:

This metering setting gives priority to the center portion of the photograph, but also takes the surrounding portions of the shot into consideration. Basically, this is a combination of Evaluative and Partial Metering. I tried to find a recent image where I have used this, but came up with none. It is useful, but I just don't really use it. 

Instead, I will attach this image. It's a visual example of the metering mode I've discussed above.

So now that we have those metering modes defined we can start discussing how to apply them. Remember, all of these metering modes are for use in Manual mode. 

Metering is one of those technical aspects that I've really focused on. It's something I love about photography. Eventually, you will have enough practice to determine  good exposure for most scenes based on your "eye".  I've done it so many times I can look at a scene and determine the proper camera setting within a half stop. It's a good practice once you've done it a few times. See if you can sit in a room and "guess" the exposure. 

Grab your camera and see how close you can get. Afterall, if you can become a human meter...it will outperform any computer! ;-) -cg