Calibrating the Voigtlander Bessa R-series rangefinder mechanism

[jaredangle]

Hey everyone, I had a slightly misaligned rangefinder on my Bessa R3A, so I took a crack at fixing it myself, and I was successful.

Before starting, mount a lens with a long focus throw (I used a VM Nokton 50mm f/1.1) and set it to infinity focus.

Step 1: Remove the spring clip in the hot shoe (you will need a precision screwdriver or similar thin tool to pop this loose, but be careful not to scratch the camera).



Step 2: Remove screws for hot shoe (Phillips head precision screwdriver, smallest size) and store in film canister. On mine, three are short and black, while top right screw is silver and slightly longer. Remove hot shoe.









Step 3: adjust horizontal alignment with smallest size slotted precision screwdriver. This is the small middle screw (three small screws will be visible through the gap underneath the hot shoe). Ensure lens stays at infinity the whole time.



Step 4: adjust vertical alignment (this will be the larger screw to the right of the horizontal adjustment.

 

[jc031699]

Did the calibration stay true?
Here’s more info in case it comes up again in the future:

J

Post in thread 'Bessa R rangefinder calibration? Done!'

Jun 20, 2024

And for the sake of accuracy I’ll say that these are likely JIS and not Phillips. So please use a well fitting screwdriver to avoid marring the heads.

• jc031699

 

[monopix]

I've adjusted a few R series but nothing recently and I haven't kept notes so I don't have much to add other than some words of caution.

My recollection is that not all the R series cameras are the same so these instructions may not be relevant to all models. It would be wrong to assume they are on the basis of just one example anyway.

My recollection is also that there is a locking screw on some which should be loosened before adjustment. I have also seen one (I think it was a R4A) that had been locked with adhesive. Maybe not a factory specification but might have been done by a previous owner/repairer. Trying to make any adjustment while the mechanism is locked is likely to cause damage. My approach, if it's a camera I'm not very familiar with, is to always remove the top cover completely so that I can inspect the mechanism, work out what screw does what and check for any locking mechanism. Only then will I attempt adjustment.