Summary
What is metering
Metering is the way your camera measures light to calculate a correct exposure.
Types of metering
Multi-zone metering
It is most likely a default metering type. It measures light levels over many small parts of the frame but covering the whole frame. Then, the algorithm decides what the exposure should be using focus area, distance etc. and matching it with the data it has. Every camera/brand has their own algorithm so it will work differently between cameras. Highlight.
When to use Multi-zone metering
This should be used for landscape, street photography or any situation where the light is not harsh.
Spot metering
It measures light in a tiny part of the frame and usually follows active autofocus area or centre of the frame. Highlight
When to use spot metering
It is useful in scenarios in extreme light conditions where you want to expose for the subject and you don’t care about the rest of the frame. It could be a portrait or moon. Highlight
Centre weighted
It is a from of multi-zone metering which focuses from the centre to the sides. It was commonly used in film photography, but nowadays, multi-zone is better than centre weighted, so there’s no reason to use it nowadays Highlight
Highlights
- Multi-zone metering, also called matrix, evaluative or segment. It could be nicknamed “smart metering” and is most probably the default metering mode on your camera. It works by measuring light levels over many small segments covering the whole frame. It then uses algorithms to decide what the exposure should look like, using all sorts of parameters (subject distance, focus area, even time of day…) and matching the scene with a database of thousands of pre-recorded images, trying to really understand what you are photographing and where your subject is in the frame. Each camera has its own algorithms which are kept secret, so from a user point of view, it may appear to be a bit “magic”. It also pays off to study how your camera reacts to each type of scene and in which situations it may guess wrong. (View Highlight)
- Spot metering is more or less the opposite: it measures light only in a tiny part of the frame (1 to 5% usually), often following the active autofocus sensor, or simply in the centre of the frame. This is very useful in extreme light conditions, as it allows you to expose for your subject without caring for the rest of the frame. The typical example is a night shot of the moon: if you use any other mode than spot, the camera will try to overexpose the very dark sky which fills the vast majority of the frame, and completely blow the highlights in the bright moon. (View Highlight)
- Finally, centre weighted metering is a form of multi-zone metering which privileges the centre of the frame to the sides. It was mostly used in the film days, when multi-zone meters were still archaic or non-existent, but there is little reason to use it anymore. (View Highlight)
(View Highlight)- AE-L/AF-L. What it does is lock either exposure, focus or both (it can be decided in the menus). If you set it to exposure lock, it will be useful when you shoot in spot mode: put your subject in the centre, press the shutter halfway to meter, then press AE-L to lock the exposure parameters, then recompose to put your subject where you really want it – as we will see later in this course, it is very boring to position a subject dead in the centre of the frame. AE-L tends to be less useful with multi-zone metering. (View Highlight)