When I first started doing photography, I was so intimidated by the fantastic photos professional photographers clicked. I learned that they used the knobby things and all the buttons that were at the back of the camera.
As I found out through the years, it wasn’t rocket science at all. Exposure, aperture, F-stop, and the dreaded camera metering are all actually quite simple to wrap your head around.
Exposure is considered to the most important thing in photography, so a lot of those buttons and knobs exist simply to help you adjust it. Metering is one such tool and, arguably, is one of the most important ones.
What is metering?
Camera metering is a way to understand the overall exposure of the scene or a part of the scene. Your camera automatically does this even when it is not in metering mode.
If you ever spotted a small dotted line with -3 and +3 on either side and a 0 in the middle, or maybe a dotted line with a minus and a plus on either side on your camera screen, congratulations! You found the meter!
What would I use metering for?
As I said earlier, the primary purpose of camera metering is to tell you the average exposure of your scene.
What will I do with the information, you may ask.
Well, you can control the exposure of the picture you are taking and adjust exactly which part of the scene is exposed and which is not to achieve the results you want. In a way, you get to control light and where it falls, which is undeniably cool.
Let’s take an example to see how exactly you can do this. If you were taking a portrait of a man in a crisp black suit, you would probably want the suit to show up as a deep black. The automatic metering system on your camera would detect a lot of darkness in the photo and try to correct it. The black would then look more dusty and ashy.
How does metering work?
Before we jump into how you do the cool light-controlling thing, let me tell you how metering works. All cameras have a default setting for the ideal amount of exposure. To get that value, the camera turns the scene into the black-and-white format, identifies the amount of light and dark areas, and averages it all out.
Camera makers usually set the perfect average value at 18% grey, based on the thousands of photographs they have studied. Your camera will try to make every scene you shoot as close to the 18% grey value as possible.
How do I read the meter?
The meter is a scale with underexposure on one end (denoted by the ‘-‘) and overexposure on the other (indicated by the ‘+’).
The ideal value of 18% is usually in the middle (sometimes denoted by a little ‘0’).
There is a little arrow on the scale that shows you exactly where along the scale the exposure of your photograph falls.
But sometimes, 18% grey is just the worst thing you can do to your photograph.
That is when you take matters into your own hands and switch to manual mode. Here, you will have a huge variety of camera metering mode options to choose from, and you can move the arrow up and down depending on how much exposure you want..
The different metering modes
There are about five main metering modes, and they can be called different things in different cameras.
For example, in a Nikon camera calls the default averaging mode Matrix Metering while Canon calls it Evaluative Metering. So you may need to scroll through all your options on your camera to know which one is which.
1) Evaluative/ Matrix metering
Evaluative or Matrix metering takes into consideration every pixel in the scene and averages it to give you the value on the metering scale. This is also what your camera automatically does, except in manual mode, you can choose the right level of exposure.
2) Multi-zone metering
In Multi-zone metering, the camera divides the scene into areas and then uses complicated algorithms to give you the value for the exposure of the scene.
With this mode, you never really know how the camera came across that value as every camera company has its own algorithm. It is essentially the same as evaluative metering but has zones that it divides the scene into first before averaging the different exposures.
3) Partial metering
If it wasn’t quite obvious from its name, in partial metering, the camera only considers a part of the scene. It only gives the average exposure for the pixels in that particular part of the scene. Partial metering is of two types– center-weighted and spot.
In this mode, the part of the photograph that is right in the middle of the scene is analyzed by the camera. It usually constitutes about 6-15%. This comes in very handy while taking portraits as you can control the exposure of your subject, who is the focus of your portrait.
In spot metering, the camera focusses on one tiny spot in the scene. This could be the tip of your nose or the wart on your chin (you never know).
It is about 5% of the entire scene and is the mode used most often by photographers. To illustrate its usefulness, I will give you an example.
If you are taking a design of say a bird against the sun. You would want to increase the exposure of the bird so its details can be seen. Even if you used center-weighted metering, the sky around the bird and the sun would be overexposed. You need to really focus on the bird to take a beautiful picture, and that is when spot metering is useful.
Well, that is metering explained. Just remember, your camera offers you many tools to get the perfect picture, it would be a shame not to use at least some of