.
Or, imagine you want to mount a lens on your camera. Viewed from the front:
- the Canon mounts by locating the lens and rotating it clockwise;
- the Nikon mounts by locating the lens and rotating it anticlockwise;
- I don't know how the Sony works.
Or imagine you want to tweak the exposure whilst shooting. You look at the meter in the viewfinder:
- the Canon reads from -2 stops on the left to +2 stops on the right;
- the Nikon reads from +2 stops on the left to -2 stops on the right;
- I don't know what the Sony does.