What are the contents and requirements of the photography sub-examination?

Look at the appearance, whether there are scratches and other traces;

Check the shutter, set it to M, and check it step by step from the highest gear to the B door. Open the lens, set the aperture to the maximum (the number is the smallest, such as 2.8 and 3.5, never set it to 22 and 32), aim at the bright place and start to release the shutter. The numbers of different gears should be changed, especially to1125 ~ 655.

When a (aperture priority) file is adjusted to a fixed value, such as F5.6, the shutter should have different changes for different light and shade;

S (shutter required, also marked Tv) file, adjusted to a fixed value, the aperture value should be different in different places;

P (Program Automatic): According to different light and dark places, the shutter and aperture should have different changes;

Lens zoom: Some lenses have zoom motors, while others don't. During manual test, the zoom ring has moderate elasticity, no shaking and no obvious noise; Focus accurately, the distance can be estimated, and then focus to see if there is any out of focus.

The flash should be able to bounce up in the case of insufficient light (some may need to be set);

Select metering mode to see if all metering modes are normal;

Take off the lens and check whether there are scratches on the mirror. , and whether there is paint stripping on the wall of the mirror box.

Actual shooting: don't open the lens cover, shoot directly, you should get a pure black picture, observe whether there are bright spots on the display screen, and try again if you can shoot white. Shoot the real scene to see if there is color cast, turn on exposure compensation, and shoot to see if there are obvious differences in each picture (normal should be different)

In a word, every aspect should be tested. Don't feel trouble, because you are God before you pay, and you are garbage after you pay. If the merchant won't let you test, you can either change to another one or let it test according to your requirements.