How to achieve "spot metering" in photography?

1. Spot metering: The camera measures light with a diameter of 3.5mm (about 2.5% of the picture). The diameter circle is centered on the current focus point, so that the off-center object can be measured (if a non-CPU lens or automatic area AF is used, the camera will measure the light from the center to the focus point). It ensures that the subject can be exposed correctly even if the brightness difference between the subject and the background is very large.

2. Spot metering can only be selected in P, S, A and M modes. In other modes, the meter will automatically select the metering mode.

3. The selection method is to press the metering button and rotate the main dial until the spot metering setting is displayed on the control panel.

Supplementary explanation:

Spot metering refers to metering a point, which is usually the center of the whole picture, accounting for about 9% of the whole picture. The advantage of this method is that it can measure the most suitable place in a certain picture according to the photographer's preference, and it is not affected by other factors, especially when the contrast between light and dark in the scene is strong, or the subject can measure the light correctly without interference from other nearby lights. For example, when taking portraits, it is absolutely necessary to measure the face. When taking a photo with a large light ratio (for example, half is in the sky and the other half is in the shadow), it is necessary to measure the part to be exposed correctly.

Because the metering point is not necessarily in the center of the composition, you need to measure the point you want to expose correctly, and then you need to re-compose the composition after metering, so there is an AE lock, which is the metering lock. After photometry is completed, you can lock the exposure, and then make composition and focus shooting. Generally speaking, your focus is basically the point where you need to measure light correctly. For the camera with point measurement linkage, the measuring point is the focus point, which can directly focus on composition and automatically measure light. If not, you need to measure light first and then focus on the above operation of composition.