The photos taken by my SLR camera always feel that there are water stains and photos to distinguish. Ask an expert to tell me what the problem is and how to solve it.

There are dust and fibers in CCD or CMOS. The easiest way is to charge the camera battery, and then turn on the dust shake mode and shake it first. If not, buy a leather tiger that blows the lens, turn on the dust removal mode, and be sure to fully charge it. Then blow carefully, don't touch CCD or CMOS, and be careful in a clean environment, otherwise the more you blow, the dirtier you get. Generally, both can be solved. If they can't work, you can only use a jelly pen. Because of the contact with CMOS, it is not recommended for unfamiliar people to operate. It is best to repair the camera.