The thing about manual rangefinder film cameras are their few minimalist controls. There's no multiplicity of dials and buttons, complex hierarchies of menus and selectable functions nor tilting/flipping/rotating screens. They are clutter free.
This is, of course, compared to modern digital cameras and there is an obvious reason for this - yep film cameras like these have no digital technology in them! Being free from the tyrannical fog of digital complexity they simply have no need any of these extra folderols.
Digital cameras in essence have within them a computer whose extensive range of complex functions have to be controlled through a human-computer interface hence the multiplicity of dials and buttons, hierarchies of menus and selectable functions and interactive tilting/flipping/rotating screens which provide this interface. Most makers of digital kit do this really badly and their camera HCIs are a bit of a nightmare to use. Plus it is often far too easy to press or twist something by accident and set something unintentionally that you might at first not notice then when you do, it is really very unclear how to unset again using the mess that is the HCI and end up wading through a multi-hundreds of pages user guide or searching the web.
Anyway, back to the elegant simplicity of the manual rangefinder film camera the Zeiss Ikon above top and its accompanying lens the Zeiss C Sonnar 50mm f1.5 ZM shown just above.
There is but one dial on the camera, located on the top right, which allows you set the film speed, switch between manual and aperture priority modes, and set shutters speeds if the former or exposure compensation if the latter. It puts all the exposure controls relating to the camera body into a single dial which is neat, ergonomic, cleverly thought out and intuitive to use.
The second control is the shutter release which has a locking collar around it which doubles as the on/off switch for the metering system. The final control is the film wind on lever which also cocks the shutter, this being a manual camera. That is it.
Now there are two other controls not on the camera that are to be found on each and every lens in the system. these are the aperture and the focusing rings. The aperture ring is the second half of the exposure control equation so to speak and to reiterated is located where it belongs, yes indeed not on the camera body but physically on the lens itself.
The focusing ring does just what it says, it allows you to focus the lens by turning the ring back and forth to superimpose the dual rangefinder image patches in the optical viewfinder.
Hence there are only five main controls on the camera/lens combination needed for its operation. Compare that to a typical digital camera with say 20 plus dials and buttons on its body, together with an LCD touch screen and a multi-layer menu system containing some 50 or more individual items all of which are used together to control the camera.
You can see why I love the elegant simplicity of my ZI rangefinder film cameras.