Before I begin, I’d like to let you know that this post isn’t only good for the T3i (600D), it’s also good for the T2i, T4i, T5i, T6i and the T7i. Oh yeah, and probably the as of yet to be released T8i. The settings in the menu area for this particular setting are almost identical for all of the cameras.
I’ll get into how to change this setting below, but first I’d like to quickly discuss metering modes in general as an understanding of this concept may help out many a new photographer quite a bit. While the default metering mode will set nearly perfect exposure for a good majority of your photos, there may be times when you need to change the mode when you’re going for very specific goals. As I explain what each mode does, try to think of instances where one other than the default “Evaluative” mode may have helped you while photographing something. I know a few different modes surely would have helped me just a few weeks ago. I was taking some landscape photos of mountains in the distance that were framed by some trees in the foreground and the exposure values that the camera chose were awful. I had to use the exposure compensation feature a lot, just to see the scene in the rear LCD screen accurately. If I had changed metering modes, I wouldn’t have had to use the exposure compensation.
Anyway, let’s get into what each of the four available metering modes means. And for the uninitiated, “metering” is when the camera assesses a scene based on a chosen mode and applies an exposure value to that scene.
Evaluative: This metering mode divides your entire scene into a grid and applies an exposure value to each sector of that grid. Then, the camera averages all of those values into one overall value and that’s the exposure for the scene. This is the default setting that comes with your T3i and again, it’ll give you good results for most of your images.
Partial: This metering mode is perfect for scenes with wildly different lighting values in different areas of the scene. For instance, say someone is standing in a dark room near an open window on a sunny day. The sun coming through that window will be so bright that it will blow out the entire scene, causing the exposure to drop way down. You most likely won’t even be able to see the person standing in the room. Partial metering takes only the center 6%-9% of the entire frame and meters based on that area. So, if you point the center of the camera at the person standing in the room, that’s the light that the camera will measure, giving you much better results than the Evaluative mode would.
Spot: If you have a very detailed scene and you need to be absolutely sure that one part of your frame will be metered correctly, this is the mode you want to use. It’s the same exact thing as Partial, but it just measures a smaller area. They say that area comprises only 2%-4% of the entire scene. So this is a detailed mode indeed.
Center-Weighted Average: This metering mode is a combination of the three above. It takes account of the entire scene, but weights the results toward the center. I’m not sure you’ll see too much difference between this mode and the Evaluative one though.
Okay, let’s get into how to set these modes. It’s super easy to do. On the Canon T3i, simply turn the camera on and then choose one of the advanced modes to shoot with, (aperture priority, shutter priority, manual mode). Then, press the Menu button on the back of the camera. From there, press the left or right arrow button on the rear of the camera until you reach the screen that has an option called Metering Mode. Once you see that, use the up or down arrow button to highlight it and then press the Set button to select it.
On the next screen, you should see four options. These are the ones I described above. To select one, use the right arrow button to highlight it and then the Set button to select it. Then, press the Menu button again (or half-press the shutter button) to exit the menu area. And that’s it. Go shoot and have fun!