Summicron-C 40mm

Does anyone know where on the web I could find a schematic of the Summicron/Rokkor 40mm? Is it like the Summicron 50 or 35?

Here is a website that has a lot of info on the CL / CLE, including

the lenses. The author makes good comments about the relative

comparison between the 40mm lenses and "true" Leica lenses...

basically, they are very well matched... comments about 30 X 40 inch

prints made with the 40. I think that you are requesting a cut-a-way

view, showing the elements... sorry, but I could not find one on the

net with all of my bookmarked leica sites. Hopefully, this site will

at least give you confidence that the lenses are great.

 

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http://www.cameraquest.com/leicacl.htm

Found a couple of other sites... still no cut-a-way view, but one

site has Chart with elements and groups.

 

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Elements / groups:

 

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http://www.cosmonet.org/camera/leiccl_e.htm

 

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Lens Compatibility:

 

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http://www.multimania.com/cesarigd/photoe2cleo.htm

A point to note here is that schematics published over the years, in

several books, such as The Leica Compendium, or the Leica Manual, or

Photgraphic Optics by Cox, show that the 50mm Summicron doesn't even

resemble itself too closely in its various versions. For this reason

it might be difficult to divine much about the 40mm, or how it

compares to other Summicrons. I should imagine it probably is a

gaussian design, with a pair of cemented groups, each having a deeply

concave surface facing each other from opposite sides of the

diaphragm; possibly a thin lens airspaced and interposed between one

or both of those concave surfaces, and the diaphragm; and single

element positive components for the front and rear elements. This is

the basic setup of the 35mm Summicron of the time period. But, then

again, the 90mm Summicron doesn't adhere to this type of formula, and

this too makes me question how much we can figure out by examining

the schematic. Why not ask some users to comment on the performance

of the 40? I think it's supposed to be good, but I've not used one.

 

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Regards,

I looked at the website Al Smith cited (I should have done this in

the first place). The lens has 6 elements in 4 groups. If you have

access to the Leica M Compendium, take a look at the 35mm Summicron

on page 51. Now, take away the thin lens just to the right of the

diaphragm, and the remaining components, I feel pretty sure, would

bear a close resemblence to the 40mm Summicron.

 

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That's the best I can do. Hope it helps.

Late response: you'll find the optical construction schematic near

the bottom of this webpage: <a

href="http://www.kscamera.co.kr/leica/m/m35.htm">http://www.kscamera.c

o.kr/leica/m/m35.htm</a>

Thanks for that good site.