Crop factor is directly related to the size of the camera sensor. Since most digital SLR cameras (DSLR) and some system cameras have a sensor 1.5-2 times lower than the standard 35mm tape (or full-frame SLR), on placing the cursor and all the standard 50mm lens, lens angle of view will be lower by 1.5-2 times. This is because the smaller sensor “cuts” only the central frame, which recorded a full-frame sensor part. Yes, and there is often used to recount millimeter lens, in fact, the lens is the image and convey the outlook is no different, only the narrow viewing angle.