Spot metering is a camera feature that allows you to measure the exposure of a specific area in your frame. It is useful when you want to control how bright or dark your subject appears, regardless of the background or lighting conditions.
To use spot metering, you need to activate it in your camera settings and select a focus point. The camera will then use the light information from that point to calculate the exposure for the whole image. You can adjust the exposure compensation if you want to make the image brighter or darker than what the camera suggests.
Spot metering is especially helpful when you are shooting in high-contrast situations, such as backlit portraits, silhouettes, or scenes with bright and dark areas. By using spot metering, you can avoid overexposing or underexposing your subject and achieve a balanced exposure.
However, spot metering also has some limitations. It can be tricky to use if your subject is moving or if you are using a zoom lens. You need to make sure that the focus point is always on your subject, otherwise, the exposure will change. Also, spot metering may not work well for scenes that have a uniform brightness, such as landscapes or skies. In these cases, you may want to use a different metering mode, such as matrix or centre-weighted metering.