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
Ko.Fe.
Lenses 35/21 Gears 46/20
Four screw holes are symmetrical. You could attach LTM mount ring four different ways.
Pre-war FED were with individually matched mounts and lenses. I don't know if all or how many.
Pre-war FED were with individually matched mounts and lenses. I don't know if all or how many.
David Hughes
David Hughes
Yes, moving the lens mount around was my first thought but then I realised that the infinity lock would move round too, as it is a single start thread. Then the viewfinder might be covered...
I asked for others' opinions because I'd like to sort out when it changed. Of course, the serial numbers would be very useful with the info.
Regards, David
David Hughes
David Hughes
To show what happens when old and new bodies and lenses are muddled up I've a photo of an elderly (1935 batch) and younger (1955 batch) FED with normally the correct lenses but swapped over to show how the RF and VF re covered.
I hope it is obvious which is which but I have my doubts...
Regards, David
I hope it is obvious which is which but I have my doubts...
Regards, David
retinax
Well-known
I think you can rotate not only the mount on the lens, which could be trouble with an infinity lock rigidly attached to it, but also the mount on the camera body.
Ko.Fe.
Lenses 35/21 Gears 46/20
This is what I exactly did at one Z4. It fixed the issue.
But OP wants to hear something else.
But OP wants to hear something else.
rfaspen
[insert pithy phrase here]
David. I understand your experiment 😎
I'm going to try it out on my fsu bodies. Has to be a Leica body cap referenced on a Leica body first, right?
As for rotating the mounts.....nope. at least on fed 1s, zorki 1s, fed 2s and some others I have, there is a recessed area (rabbet or rebate for you UK folks) at the top that makes way for top plate. I know because I once had that same idea of rotating.
I'm going to try it out on my fsu bodies. Has to be a Leica body cap referenced on a Leica body first, right?
As for rotating the mounts.....nope. at least on fed 1s, zorki 1s, fed 2s and some others I have, there is a recessed area (rabbet or rebate for you UK folks) at the top that makes way for top plate. I know because I once had that same idea of rotating.
rfaspen
[insert pithy phrase here]
Oh. Perhaps others were talking about rotating the mounts on the lens itself? I did once have an I22 that someone had reassembled the focus helicals into the wrong start. An hour or so of trying to get it into the correct starts (try and try again) and now all is good. So something like that?
David Hughes
David Hughes
Thanks for all your comments, here's my general sort of comments.
The lens flange on the body and the thread on the lens will only engage one way and so moving the mount on the body by 90° will move the infinity lock round by 90° also and mess up your focussing. Or rather it will make it awkward to focus as the tab will be in an odd place.
As for the body cap I just picked one out of the box, screwed it in and then stuck the sticker on it at 12 o'clock. In other words an easy, simple way. Once it was on I checked with the IIIc and M9 and it ended up at 12 also. So I used it as a benchmark, yardstick or reference point.
The fun started with the old USSR made ones. Thinking about how it might be made in the factory I looked for a marker on the body mount and they all have one.
For anyone interested I once spent some time talking to two elderly engineers who were apprentices before the Great War (1914-18) and they explained how things were done then and so I used their comments to work out how the mounts were made. A a result I realise you have to have the right parts and can't change things without recutting the thread and that isn't possible with ease.
Dismantling the lens and then restarting the helix elsewhere would work after a fashion but not completely and the scale and DoF indicator would be U/S.
It looks as though KMZ started with the right idea and copied the Leitz positioning exactly, FED seemed to go their own way and then came slowly into line. That's odd as they (or VOOMP) made interchangeable lenses for the cameras.
Apologies if this is a bit incoherent but it's been a long day...
Regards, David
The lens flange on the body and the thread on the lens will only engage one way and so moving the mount on the body by 90° will move the infinity lock round by 90° also and mess up your focussing. Or rather it will make it awkward to focus as the tab will be in an odd place.
As for the body cap I just picked one out of the box, screwed it in and then stuck the sticker on it at 12 o'clock. In other words an easy, simple way. Once it was on I checked with the IIIc and M9 and it ended up at 12 also. So I used it as a benchmark, yardstick or reference point.
The fun started with the old USSR made ones. Thinking about how it might be made in the factory I looked for a marker on the body mount and they all have one.
For anyone interested I once spent some time talking to two elderly engineers who were apprentices before the Great War (1914-18) and they explained how things were done then and so I used their comments to work out how the mounts were made. A a result I realise you have to have the right parts and can't change things without recutting the thread and that isn't possible with ease.
Dismantling the lens and then restarting the helix elsewhere would work after a fashion but not completely and the scale and DoF indicator would be U/S.
It looks as though KMZ started with the right idea and copied the Leitz positioning exactly, FED seemed to go their own way and then came slowly into line. That's odd as they (or VOOMP) made interchangeable lenses for the cameras.
Apologies if this is a bit incoherent but it's been a long day...
Regards, David
Philip Whiteman
Well-known
It's tangential to your observations about USSR lenses, David but the start point for screw Leica lenses is actually marked on the body flange by an engraved line on the outer edge (visible in the 9.00 position, looking at your original illustration). With Leica lenses at least, you just line up the focus index dot with the lens, and on it goes. Took me years to discover this!