Mamiya 7: Rangefinder Calibration Setup with One Meter Target
Originally posted on Instagram. Notes from the repair bench, kept here as a searchable archive. View the original on Instagram
I am often asked about rangefinder calibrations on the Mamiya 7 and it is the most common service that I do on these cameras.
The Mamiya 7 has three points for rangefinder calibration: infinity, one meter and vertical. All cameras get checked for these three points on intake. Of course, the lenses each get checked independent of the body. The particular camera shown in the photo needed infinity and one meter adjusted (important if you are shooting wide open at close distances).
This photo shows my setup for checking and adjusting the rangefinder on the Mamiya 7. The camera is placed on an optical bench with a target one meter distant. The target consists of two lines spaced exactly 60mm apart (this is the rangefinder base on the Mamiya 7). With this target at one meter I can check and calibrate the rangefinder for infinity and obviously for one meter.
While I could go outside for an infinity target, this setup allows me to easily adjust the rangefinder in the shop without going back and forth to the outside world so it is a more efficient of my time.
The 60mm spacing allows for adjustment on the Mamiya 7 but I have a target for the Mamiya Universal with different spacing when it is needed.
