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Screw Mount Summaron f2.8 goggles removed


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I've bought a L39 screw mount 35mm f2.8 Summaron with no goggles, s/n 210####, it is yet to arrive. I've noticed on wiki that this lens focuses down to .7m, yet going by the photos on the barrel of my lens it shows .65m. It has been suggested by LCT, a learned poster on this site that a previous owner might have had the goggles removed, which was not uncommon. However to do this there should be some modification to ensure the focussing will still work. When the lens arrives is there a quick way to tell if this modification has been done? Is there a physical feature to look for or do I run a test of some sort?

 

The lens will be used on an ME.

 

 

Colin

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I've bought a L39 screw mount 35mm f2.8 Summaron with no goggles, s/n 210####, it is yet to arrive. I've noticed on wiki that this lens focuses down to .7m, yet going by the photos on the barrel of my lens it shows .65m. It has been suggested by LCT, a learned poster on this site that a previous owner might have had the goggles removed, which was not uncommon. However to do this there should be some modification to ensure the focussing will still work. When the lens arrives is there a quick way to tell if this modification has been done? Is there a physical feature to look for or do I run a test of some sort?

 

The lens will be used on an ME.

 

 

Colin

 

 

Goggles were only made for M-lenses to be used on Leica M3.

Never heard that under the M-Bajonett of an M-Summaron 2.8-35mm might be a ltm-M39-screwmount like Schneider produced with the Super-Angulon-M 4.0-21mm.

But perhaps the experts know a lot more.

Normally with a well fitting M39-M-adapter you should get sharp photos, if nothing else is wrong with this old Summaron-M39.

When the Summaron was produced in 1965 - so it's a late one - Leica might perhaps run out of rings with .7-engravings, so they took one of the M3-series with .65-engraving.

That seems to be quite nomal at that days, for example my M3 made in 1966 has got some outer parts already in the design of the later M4 and Leica told me that's absolute original.

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I have all 3 variants of the 35mm f2.8 Summaron, the LTM and the M both with and without goggles. The LTM version only focusses down to 1 metre, whereas the M versions focus to 0.7/0.65 metres. An 'LTM' item which will focus down to 0.65 metres is a 'with goggles' version of the M with the goggles removed. The M mount on that version is part of the goggles. The only issue I would foresee is that the lens may not focus that well on an LTM camera as it would not have been tested on that at the manufacturing stage. With an M mount camera, such as the ME, it should be OK with a suitable M mount adaptor, but testing would be needed to establish this.

 

William

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Many many years ago (>20...) I bought a Summaron 2,8 in screw Mount with focus to 0,65 m... it DID NOT focus correctly both on LTM and M bodies : it's a typical problem of lenses made originally with goggles (and the "0,65" Summarons were goggled, indeed.. the screw Mount ones focus to 1 m). I remember that time ago there was some thread on the matter in the forum... I don't remember well... maybe the problem is the RF cam step... at infinity it is OK (of course) but error enters while focusing at shorter distances.

 

The problem can be fixed by some experienced lab... at a cost (which makes the operation not so Worth... btw, it anyway results in a not "factory original" item)

 

Can be that your item had been already fixed...if you don't have a digital M body for a quick verification, you can always verify the RF focusing comparing measured distance (looking at the focus scale at RF coincidence) and real distance... not a complex setup to put together (tripod and a measuring strip)

Edited by luigi bertolotti
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I am pretty sure that your lens will not focus correctly. It was a goggled lens to start with, and goggled lenses require the (de)magnification of the goggles to focus correctly. Someone must have removed the goggles to have the lens appear as a much rarer and therefore more expensive LTM lens.

 

Andy

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I found the old thread on the Summaron 2,8 with goggles (and factory M adapter) removed, which evidenced the problem of focusing :

 

http://www.l-camera-forum.com/topic/51140-summaron-28-with-googles/

 

see post #6 : the trick is that the factory - fit Bayonet Mount adapter is a single piece with the support for goggle : so it's easy do remove adapter + goggles and obtain a "fake" LTM lens... on your item there ought to be a small hole on the screw Mount, used to fit the small screw that retains the factory BM adapter.

Edited by luigi bertolotti
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I found the old thread on the Summaron 2,8 with goggles (and factory M adapter) removed, which evidenced the problem of focusing :

 

http://www.l-camera-forum.com/topic/51140-summaron-28-with-googles/

 

see post #6 : the trick is that the factory - fit Bayonet Mount adapter is a single piece with the support for goggle : so it's easy do remove adapter + goggles and obtain a "fake" LTM lens... on your item there ought to be a small hole on the screw Mount, used to fit the small screw that retains the factory BM adapter.

Thanks for the link Luigi, the weight of opinion is that the goggles have been removed, now the question is will it focus? I bought it from a Leica specialist dealer in Prague which any Leica user who has searched for a lens on fleabay would be well aware of. Given their apparent Leica knowledge I'm hoping they made the necessary checks to confirm the lens focuses, but no mention of this in the item description. Now I'm very interested to see what turns up.

 

Just one observation, from what ive seen online a lens with goggles has a flat/level area on the top of the lens to accommodate the goggle design, is this true for all goggle lenses because the one I bought shows no sign of this. I'll post photos of the lens to help with this.

 

Colin

Edited by colin_d
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Thanks for the link Luigi, the weight of opinion is that the goggles have been removed, now the question is will it focus? I bought it from a Leica specialist dealer in Prague which any Leica user who has searched for a lens on fleabay would be well aware of. Given their apparent Leica knowledge I'm hoping they made the necessary checks to confirm the lens focuses, but no mention of this in the item description. Now I'm very interested to see what turns up.

 

Just one observation, from what ive seen online a lens with goggles has a flat/level area on the top of the lens to accommodate the goggle design, is this true for all goggle lenses because the one I bought shows no sign of this. I'll post photos of the lens to help with this.

 

Colin

 

You may be thinking of the 50mm DR (Dual Range) Summicron which has a flat area on top to enable the removal of the goggles which are only used for close up work. The 35mm Summaron has no flat area on top as the goggles are intended to stay on. The bottom of the goggles is a round shape to fit with the top of the lens.

 

William

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I am the original 'culprit' of post no.6 which Luigi refers to above. And can confirm that there is no way a 35mm Thread Mount lens which originally started as a 'goggled' M Mount lens, will couple to the RF correctly at any other distance but infinity. The focusing helicoid and rangefinder cam are cut differently on goggled lenses - the only way to focus such a lens is by a 'guesstimate'.......

 

The best way to check an 'ungoggled' lens is to mount the camera on tripod, setting the lens distance scale to 1m and measuring the distance to the subject with a tape measure to make sure that the film plane is 1m from the subject. Once set up, check the rangefinder image - you will see that is does not coincide. If I recall correctly, a 'goggled' lens that has been 'ungoggled' will match its RF images when the distance scale is at 70cm but the camera is 1m from the subject. This, as I mentioned above, is due to a differently cut RF cam to allow for the 0.7 magnification of the goggles.

 

It could be that the dealer in Prague was not aware that the lens started its life as and M3 goggled version. But - a lens with a 210#### serial number (1965-66 vintage) was never available is screw mount. And a knowledgeable Leica dealer should know that.

 

Cheers,

 

Jan

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Popular opinion is that the lens once had goggles, here are three images of the lens, hopefully they are good enough to confirm one way or the other, once and for all, the question at hand.

 

 

 

 

 

 

 

 

 

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Edited by colin_d
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A genuine LTM 35mm f2.8 Summaron will only focus to 1 metre. This looks like a goggled version with the goggles removed. You may have issues with focus as indicated above. Somebody may have some ideas about suitable modification or adaptors.

 

William

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I suspect you will be better off sending it back for a full refund with postage.

 

The vendor would know that this modified lens will not focus via rangefinder, as it is, on either an LTM or an M Leica. Unless this fact was disclosed explicitly, they should never have sold it to you as a viable lens.

 

A working 35/2.8 Summaron is a wonderful lens, and well worth pursuing. I don't think this is the one for you, unfortunately.

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... But - a lens with a 210#### serial number (1965-66 vintage) was never available is screw mount. And a knowledgeable Leica dealer should know that.

 

Cheers,

 

Jan

 

Jan,

 

Everything you say is correct except for that last sentence. Leica did in fact make screw mount lenses on special request for quite a while even after they were officially discontinued. Some years ago a member of the German forum sold his 8-element Summicron 2/35mm lens in screw mount, and it had a 2 2xx xxx serial number! And I have seen other screw mount lenses with serial numbers exceeding 2 000 000, too (and I am not referring to the later screw mount versions of the 2/35 asph, 2/50 version IV and 1.4/50 that were originally produced for the Japanese market).

 

Cheers,

 

Andy

Edited by wizard
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wizard, on 21 Mar 2017 - 03:44, said:

Jan,

 

Everything you say is correct except for that last sentence. Leica did in fact make screw mount lenses on special request for quite a while even after they were officially discontinued. .........

 

Cheers,

 

Andy

 

Andy,

 

I fully agree, you are absolutely correct.

 

I know I was 'sitting on a weak branch' when I made that statement - I should have added "... a lens with a 210#### serial number which focused to 65cm (1965-66 vintage) was never available is screw mount...". The only excuse I have is that it was past midnight my time when I wrote it.

 

To Colin - a tell-tale sign of the lens having been a goggled version will be a small mark in or just above the thread area, at the 6 o'clock position. The goggled bayonet mount had a small 'grub' screw, which prevented it from turning accidentally; this screw usually leaves a mark after being removed.

 

And - hello again to the 'oldtimers' - you know who you are... :)

 

Cheers,

 

Jan

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Andy,

 

I fully agree, you are absolutely correct.

 

I know I was 'sitting on a weak branch' when I made that statement - I should have added "... a lens with a 210#### serial number which focused to 65cm (1965-66 vintage) was never available is screw mount...". The only excuse I have is that it was past midnight my time when I wrote it.

 

To Colin - a tell-tale sign of the lens having been a goggled version will be a small mark in or just above the thread area, at the 6 o'clock position. The goggled bayonet mount had a small 'grub' screw, which prevented it from turning accidentally; this screw usually leaves a mark after being removed.

 

And - hello again to the 'oldtimers' - you know who you are... :)

 

Cheers,

 

Jan

 

Hi Jan nice to hear about you

There are some with BM mount with a little screw on the side, removing this little screw the BM part can be unscrewed and so the lens can be used as an LTM one

even they are scaled to 70 cm you stop adjusting the range finder at 1 meter btw in this kind of lens there is a small hole in the threaded part of the lens where the little screw sit.

I confirm if necessary that the one coming from the googled for M3 does not work without googles mounts on LTM cameras

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colin_d, on 21 Mar 2017 - 01:23, said:

Popular opinion is that the lens once had goggles, here are three images of the lens, hopefully they are good enough to confirm one way or the other, once and for all, the question at hand.

 

Colin,

 

The one obvious sign that this is not an original LTM lens is the distance scale with 65cm closest focusing point. That is a dead giveaway.

 

It could have been an M lens designed for the M2 or M4, which had the mount removed (M2 and M4 had finders with 35mm frames and did not need the goggles; only M3 models did). If that is the case, it will focus correctly on LTM cameras, from infinity to about 1m but not any closer. LTM cameras had a shorter rangefinder base than the later M bodies - this affected close focus accuracy. Because of this, closest focusing limit on LTM lenses was 1m.

 

You should look at the lens mount threads in the 6 o'clock position of the lens - directly opposite the triangle focusing mark. If you can, post a close-up photo of the area. In the depths of my hard drive I found a photo of the identical mount that could have been a part of your lens - you will see the tiny screw I am referring to. This would have been a Summaron 2.8/35mm which I sold years ago.

 

Cheers,

 

Jan

 

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Hello Everybody,

 

The movable patch of the rangefinder on screw mount Leicas & on most M3's only travels from Infinity to 1 meter.

 

To have a 35mm lens focus closer on an M3, what the engineers at Leitz did was: Build a mechanism that would physically move the lens from where it was focused on an image plane at Infinity to where it was focused on an image plane at 0.65 meters while the cam in the lens moved the rangefinder patch in the camera reflective of a distance from Infinity to 1 meter.

 

This lens was attached to a set of "goggles" which fit over both the rangefinder window & the viewfinder window. These "goggles" expanded the angle of coverage of the viewfinder by a factor of 1.5X. This meant that everything seen thru the "goggled" viewfinder was now seen as being 1.5 times wider & 1.5 times further away. Things also appear to be smaller.

 

The 50mm frame lines seen in the viewfinder now showed the field of coverage of a 35mm lens.

 

Because of the minified image coupled with an unaffected rangefinder & unaffected frame lines: The subjects being viewed were now seen by the rangefinder as being 1.5 times as far away as they appeared to be without the goggles.

 

Therefore when the rangefinder mechanism said it was measuring 1 meter it was actually measuring a distance of  approximately 0.65 meters.

 

The lens mount is engraved accordingly.

 

Best Regards,

 

Michael

 

Note: 1 divided by 1.5 is 0.666666+. This is the reduction of viewfinder magnification by the "goggles" to the original system.

 

Note: The 0.91X viewfinder image magnification of an M3 multiplied by 0.666666+ = approximately 0.60X. This is the viewfinder image magnification in the range/viewfinder window of an M3 with "goggles".

Edited by Michael Geschlecht
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