Difference between digital SLR camera and mechanical SLR camera

The biggest difference between traditional film camera and digital camera lies in the difference of imaging principle: the former relies on film to sense light, while the latter uses electronic photosensitive elements (CCD or CMOS). Because the digital camera can't leave the electronic circuit, it is decided that it can't abandon the battery; The traditional film camera can use pure mechanical device, manual film winding, manual focusing and full manual, so it can abandon the battery, which is very helpful for photographers taking pictures in bad weather. For example, in Antarctic photography, the battery may not work normally because of the low temperature, but the purely mechanical traditional film camera is not affected at all, which is why some photographers still love the traditional film camera. It is estimated that although the market of traditional film cameras is shrinking,