What is Metering – and is it Relevant in 2018?
Modern age, modern tools, modern masters; the only thing that stays unchanged is the rules of the game. One of the ignored rules in the age of eye-popping megapixels, higher dynamic ranges, and fine post-processing is the metering. Yet, it is one of the tools that separate the men from the boys, the best from the rest.
Metering – defined in simple terms – is reading the amount of light to correctly expose an image.
Yes, metering is about reading the amount of light, and determining the correct exposure for a particular image. This is done via light meters. It is important to note that all modern day cameras have an in-build light meter – including mobile phone cameras. There’s also a separate light meter device available in the market.
There are two types of light meters:
- Incident Light Meters
- Reflective Light Meters
Incident Light Meters, once a necessity, are now limited to a smaller percentage of photographers.
The earlier times, when cameras weren’t equipped with light meters, a light meter was a necessity, used to measure incident light on subjects. It is a small device that determines that determines the aperture if you provide shutter speed and ISO, or shutter speed if you provide aperture and ISO. In short, it helps complete the exposure triangle for the perfect incident light. The one area of photography, which can’t live without light meter, is studio photography, where incident light reading becomes essential to get the correct exposure.
Reflective Light Metering is what most photographers rely on to make pictures in the present age.
Reflective light is the light as seen and captured on camera sensors. Since light meters aren’t required everywhere, and even can’t be used at all locations – this builtin metering has revolutionized photography ever since its first presence was felt. There are three major types of metering modes – although some manufacturers have more than three.
- Evaluative or Matrix Metering
- Center-Weighted Metering
- Spot Metering
- Partial Metering
Evaluative or Matrix Metering is the mode which camera has on by default – and hence used by a majority of present-day photographers.
This type of metering can get the job done in most situations. It meters the light evenly through the frame by dividing it into equal blocks – but giving more emphasis to the focus point areas. There are different ways the processors actually work, and some also take into account similar images taken, while others do it more evenly.
Center-Weighted Metering is the mode where an emphasis is given to reading the center of the frame correctly.
This metering mode is of particular use in backlit photography where the subject is in the center of the frame. In what will be an otherwise impossible metering situation, this will help gain the correct exposure for such an image.
Spot and Partial Metering are similar to each other, only differ in size.
Spot metering is the mode for wildlife and action photographers. In this mode, the exposure reading is taken from about 4-5% of the area around the central focus point. Bird photography, in particular, is something that gains from this metering. Partial metering is similar to spot metering, only the exposure reading area is about 8-10%.
All metering modes in camera are mere guides, and one must understand they tend to neutralize whites and blacks towards grey. To use metering, one needs to understand it first, and also the exposure compensation, to make the best use of this amazing tool.
If you do not know where the metering button on your camera is, refer to your manual. It takes 2-3 minutes to figure out how to change to the different metering modes, then another 5 minutes to take some practice shots. Compare photos taken in Matrix mode with those taken in center weighted mode.