Archived posting to the Leica Users Group, 2000/11/03
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]First of all I think that both Walt and Jim are completely correct. The most common rangefinder adjustments are: - - the rangefinder distance calibration, comprising infinity and close focus adjustments, and - - the rangefinder vertical alignment. All these adjustments can be done without the top plate coming off. The vertical alignment is adjusted through the "red dot" on cameras equipped with it, otherwise through the cover screw located directly above the lens mount. In the early cameras, it is a simple adjusting screw but on the later cameras (M4-2 and up) it is an eccentric cam that requires a special tool. The rangefinder distance calibration is done by the eccentric pivot of the rangefinder arm and the eccentric mounting screw of the rangefinder arm roller. The roller position determines the starting point of the rangefinder arm travel (infinity) and the eccentric pivot adjusts the ratio of rangefinder movement to lens cam movement by varying the length of the arm. A shorter arm gives you a larger movement of the rangefinder pivot for a specific amount of lens cam movement; and, a longer arm gives you less movement of the rangefinder pivot for a specific amount of lens cam movement. Simple! There are also rangefinder travel stops but we hardly have to go into that now. see part two