Influence of background brightness on average photometric accuracy

Background light and shade have a great influence on the accuracy of average photometry.

Brief introduction of average photometry;

Average metering is the most important metering mode in digital cameras, and almost all DC's have this mode built in.

Some cameras also call average photometry "matrix photometry" or "multiple photometry", all of which are divided into 64 or 128 areas in the picture vertically and horizontally. According to the average gray level of 18%, it is considered as correct exposure, and the results of aperture and shutter speed are given. Another way of saying this is the central key average metering, which takes the central area as the main metering basis and then averages it to other areas.

Features:

Advantages: The advantage of this method is that you can easily get a balanced picture without local highlights, and the histogram of the whole picture is balanced.

Disadvantages: The disadvantage of average metering is that it can't satisfy many situations, such as shadows, backlighting and so on.

Photometric method:

Most digital cameras or traditional fool cameras have these metering methods: center average metering, center part metering, spot metering, multipoint metering and evaluation metering. These photometry methods can basically deal with all shooting, but in the photo studio and some professional occasions or advertising shooting, photographers still have to rely on the value of the exposure meter to shoot.

Central average measurement:

Central average metering is the most widely used metering mode, and almost all camera manufacturers regard it as the default metering mode. Central average photometry mainly takes into account that general photographers are used to putting the subject, that is, things that need accurate exposure, in the middle of the viewfinder, so this part of the shooting content is the most important.

Therefore, the sensory elements responsible for metering will organically separate the overall metering value of the camera, and the metering data in the central part accounts for the vast majority, while the metering data outside the center of the screen plays an auxiliary role in metering as a small proportion. After the processor of the camera weights and averages these two values, the photographed camera photometric data is obtained.