Leica Showcase Leica 5cm F1.5 Summarit-M

BrianS

Legend
Jul 7, 2010
The Summarit-M is essentially a coated Xenon 5cm F1.5, designed during the 1930s. Leica's first-superspeed lens. This lens has a reputation for being soft wide-open, improves by F4. I've taken 5 of these apart, currently own 2 and a "half". All of them were marked 51.1mm, slightly shorter than the Leica standard. They were also optimized for F2.8 for close-up, and were in focus at F1.5 at infinity.

So I changed this one, moved the rear group back 0.2mm. This optimized the lens for F1.5 close-up, and increased the focal length ever-so-slightly.

before_mod_f15 by fiftyonepointsix, on Flickr

before_mod_f15_crop by fiftyonepointsix, on Flickr

close_test_f15 by fiftyonepointsix, on Flickr

close_test_f15_crop by fiftyonepointsix, on Flickr

Before and after applying this modification, all at F1.5.
 
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Amin

Hall of Famer
Jul 3, 2010
I've been looking at this lens on Ebay as well. Looks like your modified lens does well at f/1.5. Are the unmodified ones very soft wide open?
 

usayit

Veteran
Sep 4, 2010
I've always loved the Summarit 50mm f/1.5... they are fairly collectable too. It is also my understanding that the coatings are relatively soft which makes finding a good one difficult. One acquaintance of mine acquired one and then spent the money to have it disassembled and recoated. It retained its character and produces surprisingly good results wide open. This has lead me to believe that many of the soft examples may be related to the aged coatings.
 

BrianS

Legend
Jul 7, 2010
The interior coatings are soft, and the surfaces on each side of the aperture were subject to becoming hazed. This one cleaned up well, was cheap because the filter ring was damaged. Essex cleaned this one, and my LTM lens as well. I've since cleaned a couple for other people.

The unmodified Summarit front-focuses about 1" at min focus, and is spot-on at F2.8. On film, not as noticeable. On digital: will drive you crazy.

Having a lens polished and recoated: expensive! Focalpoint polished and recoated one of my collapsible Summicrons, a very early one with "hot glass". It was like wax paper, now looks like new. ~$200 for the job- one element. On a typical Summarit: you would only need to do the surface behind the aperture blades. I think the oil gets to it, the surface behind the aperture is close to the mechanism.
 

BrianS

Legend
Jul 7, 2010
I've been asked about the modification that went into my Summarit. There is no easy way to shim this lens, as can be done with the Jupiter and Nikkor lenses. I've taken 5 Summarits apart, all were marked 51.1mm. Why make it shorter than the standard 51.6mm? Possible to deal with focus shift. The lens front-focuses when used at F1.5 at minimum distance, but is in-focus at infinity. Increasing the spacing between front and rear sections "slightly" increases the focal length, and moves the rear towards the image place.

Step 1: take out set screws.

Remove_Cover_Screw by fiftyonepointsix, on Flickr

Step two: use a screwdriver to lock the rotating sleeve into place so that the optics module can be unscrewed.

Set_Screw_Access by fiftyonepointsix, on Flickr



Step Three: Unscrew the optics module.

Hold_in_Place_Unscrew_Module by fiftyonepointsix, on Flickr

Step 4: Take out the rear retaining ring:

rear_ring by fiftyonepointsix, on Flickr

Step 5: Unscrew the front section, hold rear with rubber mat or cork.

get_a_grip by fiftyonepointsix, on Flickr

Step 6: Front section is out, you can push rear modules out.

Front_Section_out by fiftyonepointsix, on Flickr

Step 7: Rear out, 0.2mm shim ready.

Shim_from_J8 by fiftyonepointsix, on Flickr

Step 8: Shim in place, this one is from a Jupiter-8.

Shim_in_place by fiftyonepointsix, on Flickr

Now, put everything back in place in following these steps in reverse order.
 
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sbp18

New Member
Feb 7, 2014
Hi brain,
Is there a pictures in your thread on opening summarit 5cm ? I cant see / access them. I only seeing question marks.

Do you have details of how to dismantle this summarit ? I have old paint falling into aperture blades that I need to clean.
Thanks
 

BrianS

Legend
Jul 7, 2010
I will look for the images- early on the forum software changed the syntax for gallery images, and a lot of the generated BB codes no longer worked.

And- welcome aboard.
 

BrianS

Legend
Jul 7, 2010
Repaired the links, the images were in the Gallery but the Syntax changed.

THIS IS CRITICAL! The aperture blades might come out if you blow too hard on them, or turn upside down. Be careful. The paint is probably the anti-reflective coating put on the front group. It peels off. I use a Black Sharpie marker to blacken the glass.
 

sbp18

New Member
Feb 7, 2014
Thank brian,
Now I can see the pictures.

Is there an additional picture showing how to dismantle further ?
If I look through the lens with flashlight underneath, can see faint fogging and around the edge show thicker fog / haze.

Thinking may as well clean them & re lube.

Thanks & appreciate your pictures + expertise.
 

sbp18

New Member
Feb 7, 2014
Also, I happen to own both Ltm version as well as M_mount version. For Ltm version its easy, I simply took out 3 screws at the bottom of the mount to re lube / grease the moving focus barrel. However, the M_mount has NO screws, only headless pin. Any clue how to deal with it ?
Thanks
 

BrianS

Legend
Jul 7, 2010
Once the optics module is out, you will see three screws on the inside of the focus mount. I have not relubed mine, but I suspect those three hold the mount on. They are spaced the same as the LTM version. There are also a retaining ring with slots at the top. Next rainy day- I need to try this.
 

Alex

Rookie
Dec 2, 2012
United States
Alex
Hi Brian. Thank you for the instructions on how to disassemble the Summarit. I am thinking about taking mine apart to remove the haze. Can you offer any advice on how to do this....I keep hearing about the surfaces being soft and the haze being hard to remove without a special solution from Germany. Also, where can I find one of those shims to optimize my lens for 1.5? Thanks......
 

Alex

Rookie
Dec 2, 2012
United States
Alex
summarit reassembled but aperture ring stuck

Hi, I ended up using alcohol and a lens cleaning cloth based on advice in another thread and it worked well. The lens is free of haze now and reassembled...only problem is that I now can't turn the aperture ring...it is stuck. If I apply a lot of pressure, the optics mount starts to move relative to the focus mount (set screws are replaced, but they are not enough to hold it). Any thoughts on how to free the stuck aperture ring? Mine is a screw mount version of the summarit 1.5 50mm.

Thanks.
 

BrianS

Legend
Jul 7, 2010
If you take out the front section, will it turn? I'm thinking there is pressure against the mechanism. I have not had to do this on a Summarit, but had it happen on a Canon 50/1.5.
 

Alex

Rookie
Dec 2, 2012
United States
Alex
View attachment 1846

Nothing turns in the front section......other than unscrewing of the front element. Based on the picture I just posted, can you tell me if the aperture ring should be able to turn relative to the rest of the optics mount? If yes, then its somehow jammed.

Earlier on, I did not realize that the aperture screws did not have to come out in order to separate the optics mount and focus mount and by taking them out, that little retainer that sits on the aperture blades fell out....I put it back in and seated it properly on the blades. However, somehow the ball bearing disappeared in the process. I don't recall it falling anywhere. Is it possible its still in there but not lined up properly with its hole on the aperture ring and that it is therefore jamming the mechanism?

Thanks,
Alex.
 

Attachments

BrianS

Legend
Jul 7, 2010
With the front section out- is the aperture easier to turn? I was wondering if it pressed against it. Same with the rear section, which is what happened to my Canon lens.
 

Alex

Rookie
Dec 2, 2012
United States
Alex
By front section, I'm assuming you mean the front element that screws in above the aperture blades. That is removed (as in the pic above) but the aperture ring still does not turn.
 

Alex

Rookie
Dec 2, 2012
United States
Alex
Ok, reassembled, clean, and working now. Somewhere along the way, the ball bearing was lost and by tightening the ball bearing screw without the ball bearing being there, it prevented the aperture ring from turning. As soon as I loosened this screw it turned freely. This is the first lens I've worked on and so I'm very happy with the outcome. Thanks for tutorial Brian. I will revisit it after I pick up a .2mm shim. Can you advise on where I can find a shim.....and a replacement ball bearing? Thanks!
 

BrianS

Legend
Jul 7, 2010
Most of the ballbearings that I've acquired came from a "now parts lens"... NEVER take the mount off a Canon FD 50/1.4 SSC, totally different from the FL lens. These were very small. Any idea how big the bearing is?
 

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