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Dual Range Summicron


Perceval

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They are identical, except for the mounting.

 

The origin of the superiority myth is probably the following. The optical cell and the focusing mount are two separate units and can be screwed apart. When the optical cell was assembled, there was inevitably some variation in the final focal length. So the actual focal lengths were measured and the cells were sorted into three groups centered on the values of 51.6, 51.9 or 52.2mm; these values were scratched on the mounting of the cell. The focusing mounts too were manufactured in three versions to take cells of these groups, and each had a code engraved on the back of the focusing lever: 7 or 18 for 51.6mm, 8 or 19 for 51.9mm, and A for 52.2mm. When you buy any rigid Summicron, it is a good idea to check these compatibility codes. Why they are so cryptic is anybody's guess.

 

Now the DR Summicron's mounts were for the middle group only, so the cell must always be engraved 51.9mm. But first, this is not an individual measure but only a group designation, and the group does probably comprise cells with focal lengths from 51.75 to 52.05mm approximately. Second, cells in this middle group are not inherently superior to the others. All have passed the acceptance tests, they are just different parts of the total variance spectrum. The outer groups are not 'faulty' in any respect.

 

This kind of selective assembly was the rule, not only in the manufacture of lenses but also of camera bodies (and microscopes etc.) because in those days, parts manufacture could not be held to the tolerances required. Each assembly worker, who was a very qualified and seriously underpaid person by present standards, had a tray full of each part he was to add, and he matched the parts for the best fit. Sometimes a slight stroke with a fine file and a tap with a wooden hammer was also required. Today CNC machinery produces parts with tolerances that nobody could imagine possible even during the 1950's, and internal adjustments in the mechanisms and mounts are enough to take care of the remaining variance.

 

But stories of what happened in the Leitz factory circulated and were blown up into mythical proportions. There was always a legend that some privileged people received especially good specimens, but it was never true. The QC was the strictest possible in those days, and every product had to pass it.

 

LB

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I add that in USA, in the much followed magazine "Popular Photography" a test on the DR Summicron was published, in which they squarely declared that it was the best 35mm lens of any time : this could have contributed to the "urban legend" of the DR as a "Summicron with something special".

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On my 50 rigid Summicron the optical cell is marked (scratched) 37 51.9. AA, with the last A as superscript. The focus mount has the serial, 1832837, properly engraved and white paint filled on the circular ring visible after removing the cell.

 

Gerry

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On my 50 rigid Summicron the optical cell is marked (scratched) 37 51.9. AA, with the last A as superscript. The focus mount has the serial, 1832837, properly engraved and white paint filled on the circular ring visible after removing the cell.

 

Gerry

 

Then if the appropriate numbers are engraved on the back of the focusing lever (see above) all is well.

 

LB

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There is '19' under the 'Germany' between the feet and m and the focus lever, only visible when the lens is focussed to close distance, I hadn't noticed it before in 25 years of using it!

It's been sharp all that time so haven't worried :-)

 

Gerry

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On my 50 rigid Summicron the optical cell is marked (scratched) 37 51.9. AA, with the last A as superscript. The focus mount has the serial, 1832837, properly engraved and white paint filled on the circular ring visible after removing the cell.

 

Gerry

 

Is a "undercover" APO ASPH !!! :D The "new" Summicron rumored of this year !!! :p They have taken lot of years before revealing it... but it was quietly prototyped 50 years ago !!!

Edited by luigi bertolotti
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They are identical, except for the mounting.

 

The origin of the superiority myth is probably the following. The optical cell and the focusing mount are two separate units and can be screwed apart. When the optical cell was assembled, there was inevitably some variation in the final focal length. So the actual focal lengths were measured and the cells were sorted into three groups centered on the values of 51.6, 51.9 or 52.2mm; these values were scratched on the mounting of the cell. The focusing mounts too were manufactured in three versions to take cells of these groups, and each had a code engraved on the back of the focusing lever: 7 or 18 for 51.6mm, 8 or 19 for 51.9mm, and A for 52.2mm. When you buy any rigid Summicron, it is a good idea to check these compatibility codes. Why they are so cryptic is anybody's guess.

 

Now the DR Summicron's mounts were for the middle group only, so the cell must always be engraved 51.9mm. But first, this is not an individual measure but only a group designation, and the group does probably comprise cells with focal lengths from 51.75 to 52.05mm approximately. Second, cells in this middle group are not inherently superior to the others. All have passed the acceptance tests, they are just different parts of the total variance spectrum. The outer groups are not 'faulty' in any respect.

 

This kind of selective assembly was the rule, not only in the manufacture of lenses but also of camera bodies (and microscopes etc.) because in those days, parts manufacture could not be held to the tolerances required. Each assembly worker, who was a very qualified and seriously underpaid person by present standards, had a tray full of each part he was to add, and he matched the parts for the best fit. Sometimes a slight stroke with a fine file and a tap with a wooden hammer was also required. Today CNC machinery produces parts with tolerances that nobody could imagine possible even during the 1950's, and internal adjustments in the mechanisms and mounts are enough to take care of the remaining variance.

 

But stories of what happened in the Leitz factory circulated and were blown up into mythical proportions. There was always a legend that some privileged people received especially good specimens, but it was never true. The QC was the strictest possible in those days, and every product had to pass it.

 

LB

 

I believe I mentioned this some years ago on the forum, but repeat it again to possibly get more information. My Japanese friends stated everything that has been said above in the 1980ties and added that the "N" that also appeared scratched into the barrel indicated a "neutral color" balance. Is there any evince to substantiate that claim?

I own several 50 mm Summicrons, including dual range, 50mm black paint rigid M and 50mm chrome screw type. All have the characteristics described above.

Teddy

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I add that in USA, in the much followed magazine "Popular Photography" a test on the DR Summicron was published, in which they squarely declared that it was the best 35mm lens of any time : this could have contributed to the "urban legend" of the DR as a "Summicron with something special".

 

Hello Luigi,

I believe that you mean Modern Photography. I believe I still have a photocopy of that article somewhere. It at at that time persuaded me to hang on to my Dual Range 50 Summicron which I still have.

Teddy

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I believe I mentioned this some years ago on the forum, but repeat it again to possibly get more information. My Japanese friends stated everything that has been said above in the 1980ties and added that the "N" that also appeared scratched into the barrel indicated a "neutral color" balance. Is there any evince to substantiate that claim?

I own several 50 mm Summicrons, including dual range, 50mm black paint rigid M and 50mm chrome screw type. All have the characteristics described above.

Teddy

 

I would be very surprised if DR lenses had a different colour balance than standards... imho is a unreal speculation.

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When the lens elements were assembled into the optical cells, no particular element was designated to go into one or the other of the focal length groups – what group the cell was assigned to was determined by measurement after the assembly. There may have been some random (but surely very small) variation in the colour transmittance of different elements, but that was in turn randomised over the entire production. So the idea that there would be enough colour variation to matter is very farfetched.

 

The colour transmittance of an optical glass is determined by the composition of that particular glass. There can't be much variance, least of all within one melt.

 

LB

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  • 1 month later...
I'm sending my DR to DAG this week to code it. What will be the correct coding? I can't seem to identify a specific code for this lens in the M9 menu system. Any suggestions?

 

The lens is today a 'working relic' of Leica history. I would think twice about adding a code, making it less original. Especially as there is no need to do this, apart from having the focal length in the Exif data. It won't change the images in any perceptible way.

 

If you feel that you must do this (Old Man furtively crossing himself) then the code of any 50mm Summicron would do. If you have another one, chose a different 50mm code.

 

And besides, Leica says that the M9 or M8 are off limits for the DR. And they are the only M cameras that do use six-bit coding.

 

The old man from the Kodachrome Age

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....

And besides, Leica says that the M9 or M8 are off limits for the DR. And they are the only M cameras that do use six-bit coding.

 

The old man from the Kodachrome Age

 

And it's TRUE... it does not focus... the "DR equivalent" combination that can work on M8/M9 is the SOMKY (SOOKY-M) with UOORF(16508) ring and a Summicron 50 (DR, in case) lenshead : same near focus capabilities, same image quality : I use it a lot on my M8.

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Edited by luigi bertolotti
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And it's TRUE... it does not focus... the "DR equivalent" combination that can work on M8/M9 is the SOMKY (SOOKY-M) with UOORF(16508) ring and a Summicron 50 (DR, in case) lenshead : same near focus capabilities, same image quality : I use it a lot on my M8.

 

Luigi,

 

I was looking for a DR-Summicron for my M9 until I read that it does not focus on the M9. Does the SOMKY/UOORF combination work with all Summicrons? I have the version IV Summicon 50.

 

Grazie.

 

Guy

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