David Hughes
David Hughes
This has been making me wonder and worry for some time; mostly because I have one that appears to be a young FED or Industar-10 lens with the modern to f/16 scale and nice coatings. Alas, it seems to fit a lot of cameras upside down with the VF blocked at times.
I couldn't work out how to find the M39 thread's start point easily and then I had a bright idea and searched instead for the finishing point.
Here's a Leica with a body cap screwed into it and an indicator pointing to TDC or the top at 12 o'clock if it was a watch or clock face.
I fixed the pointer securely, if untidily, and then checked all my screw threaded Leicas and some M series ones using a screw to bayonet adapter. They all finished pointing to 12 o'clock.
Now the fun starts; in a 1936 FED the pointer ends up at 5 o'clock but the 1936 lens (Industar 10) is the right way around.
In FED cameras dating from the late 1930's to the early 1950's the pointer ends up at 9 o'clock but the lenses from those cameras work properly.
Finally in bodies (FED, Leningrad and Zorki) dating from the mid 1950's to the youngest ones I have (mid to late 1960's) the pointer ends up like it does on the Leicas at 12 o'clock. There were a couple of odd ones at 11-ish. And all the lenses from those cameras work properly.
I guess the lens that started this all was either modified with an old focussing scale to fit and early FED camera or else some wicked seller made up a few bits and pieces to look OK for a sale...
I'd be very interested to know what others' cameras do but it is important to set the benchmark or pointer on a Leica.
Regards, David
I couldn't work out how to find the M39 thread's start point easily and then I had a bright idea and searched instead for the finishing point.
Here's a Leica with a body cap screwed into it and an indicator pointing to TDC or the top at 12 o'clock if it was a watch or clock face.

I fixed the pointer securely, if untidily, and then checked all my screw threaded Leicas and some M series ones using a screw to bayonet adapter. They all finished pointing to 12 o'clock.
Now the fun starts; in a 1936 FED the pointer ends up at 5 o'clock but the 1936 lens (Industar 10) is the right way around.
In FED cameras dating from the late 1930's to the early 1950's the pointer ends up at 9 o'clock but the lenses from those cameras work properly.
Finally in bodies (FED, Leningrad and Zorki) dating from the mid 1950's to the youngest ones I have (mid to late 1960's) the pointer ends up like it does on the Leicas at 12 o'clock. There were a couple of odd ones at 11-ish. And all the lenses from those cameras work properly.
I guess the lens that started this all was either modified with an old focussing scale to fit and early FED camera or else some wicked seller made up a few bits and pieces to look OK for a sale...
I'd be very interested to know what others' cameras do but it is important to set the benchmark or pointer on a Leica.
Regards, David