MM true but kinda not true. If you look at the focal length typed or etched into the side of the lens, ALL LENSES are in a "full frame" or "35mm film" focal length format. To include APSC specific lenses, they also have etched in to the side a FULL FRAME equivalent focal length. As you put these lenses on different digital sensor sizes or film gate size cameras, this is when your FOV changes. This is called crop factor. ALL sensors/film gates that are NOT Full Frame or old 35mm film size have a crop factor. You kinda can't ignore this lol. A 16mm film gate found in an Arriflex S16 has a x3 crop factor. An APSC or Super 35mm film gate has a crop factor of 1.5. When mounting a 35mm lens on a Bolex H16 (16mm film motion picture camera) your FOV would be equivalent to looking into the viewfinder of a Canon 1DX Mark II with a 105mm lens mounted onto it. Or "105mm FF equivalent". Hope this helps.
