Can the SLR lens be installed on the SLR without taking it off?

The correct way is to install a common lens on the fuselage (for example, 24-70 focal length from wide angle to medium focus), put it in the camera bag and take it out for use. Repeated loading and unloading of lenses has many disadvantages: it is easy to get into dust; Will increase the wear of parts at the bayonet; Increase the probability of hitting the lens. Therefore, it is necessary to change the lens as little as possible and load and unload the lens less. Pay attention to the following points when putting the camera into the camera bag: 1, the lens should be completely retracted; 2. Open the lens cover; 3; If the lens is placed upward, grab the fuselage when taking it out, and don't grab the lens to take it out; 4. Immediately after taking out the camera, hang the camera strap around your neck.