Original 35mm Summilux - design changes

[scsambrook]

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I recently re-discovered some notes I made on a Leitz dealer training course in London, in either 1968 or 1969. Amongst them is one stating that the then-current 35mm Summilux had recently been improved so that its image quality matched the contemporary 35mm Summicron at similar apertures. I've not seen any other reference to such a change, but then I've not read everything . . . Can anyone provide any more information about what was done, and when?

 

I got a chrome 35/1.4 around 1965/6 (not an easy task as they were always in short supply) and wasn't greatly impressed with it. Even allowing for its then-extreme specification, it certainly wasn't as sharp or as bright as the 35mm Summicron which I got to replace it. But the black 35mm Summilux I had much, much, later was certainly at least as good as the chrome Summicron.

[adan]

Everything I can find indicates that the basic optical formula (glass shapes and positions) did not change, from introduction in 1961 until retirement in the 1990's.

 

(There was a version change in 1966, but this was basically operational things like the lens-hood type and fitting, and the elimination of the infinity lock in the focus tab).

 

However, there were two significant changes in coating technologies, industry-wide, in and around the late 1960's.

 

- adoption of vacuum vapor-deposition techniques in place of liquid "dip" coatings.

- adoption of multi-coating (Zeiss T*, Rollei HFT, Pentax SMC, Canon SSC)

 

The second was more or less dependent on the availability of the first, which produced harder and thinner coatings, allowing more layers to be superimposed.

 

Coating improvements would definitely increase contrast and "brightness." They would not directly increase absolute resolution, but reduced overall flare would increase MTF at the margins, revealing resolution that previously got lost in the "fog."

 

Leica has never bothered to "name" or otherwise publicize coating techniques, as have Zeiss and the others mentioned. So it isn't clear exactly when they would have adopted these for any particular lens. But they certainly might have mentioned it in the context of "improved imaging" at your training course.

 

Incidentally, the v.4 35 Summicron (1979) actually borrowed from the Summilux design the seventh meniscus element immediately behind the aperture blades. This reduced field curvature among other things.

[pgk]

Everything I can find indicates that the basic optical formula (glass shapes and positions) did not change, from introduction in 1961 until retirement in the 1990's.

The wiki on this forum shows two versions with two designers accredited for the first version and two for the second! I've not checked this but obviously the 'version change' if that is what it was, might have included optical modifications, better coatings or reduced tolerances I suppose?

[adan]

Yes - but on the other hand, Erwin Puts' Compendium gives one optical drawing and performance description covering the entire history of the lens, saying of the 1961 design, "it stayed in production until 1996."

 

And he is pretty rigorous about identifying even small optical changes/versions - where they exist. E.G. the varieties of 135 f/2.8s or 90 f/2s or 35 Summicrons.

 

The two versions in the wiki show operational and cosmetic/structural changes of the barrel (which I mentioned in my previous post, based on the wiki images). But say nothing about any optical change.

 

Edit - per Laney "Leica Collectors Guide" (1992), on the 1961 35 f/1.4: "The longest lived M-lens. The seven-element optical design...has remained unchanged. Only the mount was altered and the external diameter reduced from 46.5mm to 42mm. ...later types had no infinity lock."

[pgk]

Edit - per Laney "Leica Collectors Guide" (1992), on the 1961 35 f/1.4: "The longest lived M-lens. The seven-element optical design...has remained unchanged. Only the mount was altered and the external diameter reduced from 46.5mm to 42mm. ...later types had no infinity lock."

OK I've checked what sources I have, and from a paper by Jonas & Thorpe (of Elcan) where the following is stated: "The ELCAN C-number identification and production dates are : C27 Summilux 35mm f/1.4 1958 1961-1992" They add : "This lens, designed in 1958 ..... 48 years later, we ..... take a second look at .....the 1958 Mandler/Wagner design..... It appears that this simple double Gauss form cannot give improved performance given the field and aperture constraints even with additional glass choices."

 

I've abridged a lot but it looks like there was one design (if people at Elcan don't know better then nobody will) and that it was a Mandler/Wagner design from 1958.

[adan]

Good find!

 

End dates for Leica lenses are always tricky because, given the low sales volumes, especially for the "exotic" stuff, and the fact Leica tends to produce a "batch" of several hundred or thousand all at one time, the lenses may be available for order, and in the catalog, years after the last one actually rolls out of the factory.

 

So the factory may know when the last one came off the line (1992) while a 1996 or 1998 brochure may still show it as a purchasable product.

[cbretteville]

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The Leica factory records show the last production run of the 35/1.4 were 3000 lenses dated 1992, serial numbers 3599701-3602700.

Carl

[scsambrook]

My thanks for the responses. I had quite forgotten what I was told on the Leitz dealer training course until I found the folder and have always thought that the lens was unchanged throughout its life. It would be interesting to be able to compare an early example with a later one, to see what - if any- differences they are. Sadly, I have neither

[lct]

I would not hesitate to choose the latest version. Due to more modern coatings, i suspect, my German sample from 1989 has less flare than v1's i've used in the past.

[a911s]

(There was a version change in 1966, but this was basically operational things like the lens-hood type and fitting, and the elimination of the infinity lock in the focus tab).

 

Actually the infinity lock on the 35 1.4 continued from 1966 to about 1969, but the the tab's latch was now bare aluminum instead of black painted bronze.