Modifying Summaron M 35mm 3.5 to 35mm frame line

[New Editor]

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Hello, everybody
Recently I`ve got the Summaron 35mm f3.5 with M mount, and was surprised that it activates the 50mm frame.
I`ve found that the bayonet can be home modified to bring up the 35mm frame. But did not see exact instruction.
Anybody could help with it?
What exactly should I file off?
Thank you.

[a.noctilux]

Welcome New Editor,

First, filing can be done, looking at the rear of your lens, the slanted one is the one to file off about 0.5 to 1mm .

But, your lens may not be the "right" one to be the "good" one to be filed.

 

The first Summaron 35mm was designed to be used with M3 so the goggles was added AND it shows the nice 50mm framelines.

I bet that this lens is one of them and that somebody had "forgotten" the added device (if it's not in the package).

In this case, without the goggles, the focus coupling with the camera would be faulty, only right at infinity setting.

Edited May 6, 2020 by a.noctilux

[New Editor]

9 minutes ago, a.noctilux said:

The first Summaron 35mm was designed to be used with M3 so the goggles was added AND it shows the nice 50mm framelines.

I bet that this lens is one of them and that somebody had "forgotten" the added device (if it's not in the package).

 

I`m sure my lens is not intended to be used with the goggles. It does not have a flat place on the top for goggles mounting.
Regarding the info I`ve found on this forum, my lens is rather the one from the 1st batches with M bayonet, and was intended to be used with an external 35mm viewfinder inserted in the accessory mount.

[a.noctilux]

Interesting,

from Wiki, Summaron 3.5cm f/3.5

if I follow you, your lens has serial number

1149101

- 1151000

Summaron 3.5 cm 1:3.5 (M3-w/o-specs)

from 1954

[New Editor]

My serial is 1 274 xxx
Made in 1955 according to the Leica wiki.

[bayernfan]

If your lens is indeed an early (pre M2) M mount without goggles, it was designed to be used on the M3 with a cold shoe viewfinder. It brings up 50mm framelines on M cameras. 

I have one myself. I sent it to DAG to have the cam professionally milled as well as a full CLA performed.  Fantastic lens in use once it brings up the correct framelines.

Given the quality of the lens, I would not hack it with a file. Have it done by a professional. 

[luigi bertolotti]

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9 hours ago, New Editor said:

I`m sure my lens is not intended to be used with the goggles. It does not have a flat place on the top for goggles mounting.
Regarding the info I`ve found on this forum, my lens is rather the one from the 1st batches with M bayonet, and was intended to be used with an external 35mm viewfinder inserted in the accessory mount.

If the minimum focus distance is 1 meter (3,5" written in the feet scale items) you can be sure it's an original ungoggled item for M3 : goggled items focus to 0,65m/2'4" even if have been ungoggled (I have a Summaron 2,8 of this "bastard" kind - RF doesn't work right on those items);

btw, your version of 1955 has some little difference from the very first items for M3. 

 

Edited May 6, 2020 by luigi bertolotti

[New Editor]

luigi bertolotti

My lens has 3.5 feet (~1m) minimal focusing distance. So I`m sure it`s a pure M3 lens.

Do you know what exact part of the bayonet lug should be filed off to bring up the 35 mm frame?

[a.noctilux]

3 minutes ago, New Editor said:

luigi bertolotti

My lens has 3.5 feet (~1m) minimal focusing distance. So I`m sure it`s a pure M3 lens.

Do you know what exact part of the bayonet lug should be filed off to bring up the 35 mm frame?

see my post #2 , the slanted claw just at left when you look at the lens from rear.

Be careful not to butcher your nice lens, take care not to let the metallic dust go inside the lens.

If by chance you have removable adapter (look at a tiny setscrew which fixes the mount), you can do the filing only on the adapter,

it would be safer work.

 

[New Editor]

luigi bertolotti

Unfortunately, the mount is nor removable. But i think it can be handled with care on the lens.

[kaspart]

Search the net about modifying a Summicron-C 40mm to bring up the 35mm frame lines. It's the same topic.