Adjusting the Jupiter-3, Jupiter-8, and others For Leica

1) I've usually found that lenses that cannot drive the RF of the camera to infinity are usually way out of spec. Poor quality control on the Valdai, I've never handled one that worked without being adjusted.

2) Yes- near focus calibration is for the Leica.

3) After adjusting the focal length, both near and far checks are required. I settle for infinity in focus as F2.8.
 
Sonnar Brian said:
That is way off! I've never seen a Nikkor off that much, they were shimmed for wide-open use. I have the three 5cm F2, 5cm F1.5, and 5cm F1.4: all were perfect on the M9.
The Canon- three 50/1.4: perfect, 50/1.5: was optimized for F2.8 and I changed it.
Click to expand...
There is something wrong with the way I was doing the focus screen film plane calibration. Not sure why. I was using a split prism focusing screen, maybe a ground glass is more accurate - I have one on order. After shooting a roll of test film, I found that the Nikon 50/2 LTM was correct without shims after all. I also removed 0.5mm from the Canon 50/1.4 LTM, so the total shim became 0.4mm for that one. It also looks like I need to modify the helicoid since both Jupiter-8 KMZ (1 silver, 1 black) lenses will not drive the rangefinder to infinity. Furthermore, the silver Jupiter-8 does not focus to infinity despite having the rear element moved 0.4mm closer in; I am hoping the helicoid modification will help it to come to infinity focus. I have so much to learn...
 
I'm far into the effort of shimming old LTM lenses. Brian, you've inspired me with your tutorials and musings.

Here is a cookie crumb for those on the hunt for lens focus viewers:

Adjusting the Industar-61L/D for the Leica

The I-61L/D is a Tessar formula lens made with low dispersion glass. Sharp and higher contrast. Also inexpensive. The optical qualities are excellent, but it is not unusual to find one that requires adjustment. This one: we are going to adjust the focus to match the distance scale, and then...
www.rangefinderforum.com www.rangefinderforum.com

Also, I've got a lead on the ground glass viewer with built in magnifier. Brian, it seems like yours is a variant / clone of the Leitz VEHIG. I am going to mock one up using the Periflex viewer and a Leica chimney viewer for the Leica Visoflex. I just have not been able to get reliable results using a Pentax split-image focusing screen and my M2..., with a digital microscope as the viewer. Not sure why.
 
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