Is it best to set the SLR photography schedule to zero?

First of all, we should understand the role of scale representation. The ruler table is the correct exposure value that the machine thinks according to the program. It synthesizes the parameters such as aperture (controlling the size of incoming light), exposure duration, sensitivity (sensitivity) and white balance (ambient color temperature), and gives the correct values through calculation.

This correct value is based on "medium gray", which can be understood as "half white and half gray" for the time being, and the three values of RGB are equal.

However, a machine is a machine, and there will be calculation errors. For example, exposure to a place with uniform light and little chromatic aberration can basically set the scale to zero. At this time, spot metering, global metering and central metering, including Nikon's high-end point-to-point combined metering, can all work normally to obtain an ideal exposure value. The point is, when you shoot a place with a large contrast, it won't work. For example, if you take a photo with backlight, the focus area will be exposed normally, and other areas will be exposed incorrectly, so there will be a special effect of overexposure behind the clear face (focusing on face metering) when you backlight. At this time, the scale is definitely not in the position of "0", but the film is exactly what the author wants.

Suggestion: If you have a camera in manual mode, use spot metering. Then, focus on the object you want to expose correctly. At this time, the parameters are adjusted to make the scale "zero", and finally the composition is taken. Basically, the main part of the photo you want will get ideal exposure, which is enough.