Is A Summicron A Summicron?

[phototone]

Yes, well I realize that is a rather cryptic title for this post. What I am wondering is this. Leica labels several focal length lenses as Summicron, and they all share a common maximum aperture F-2. Is this all the similarity there is. Are they all different optical designs depending on focal length, or do they share any common design heritage beyond the goal of the same maximum f-stop? Does Leica attempt to get the resolution in the same range, or contrast or other criteria?

 

[Gabriel M.A.]

Hi Phototone: short answer -- The naming convention is mainly based on the maximum aperture. If they were based on the optical formula, contrast, etc., the Leitz 50mm f/2 would have changed names many times already.

 

[phototone]

Hi Phototone: short answer -- The naming convention is mainly based on the maximum aperture. If they were based on the optical formula, contrast, etc., the Leitz 50mm f/2 would have changed names many times already.

Well the 50 f2 DID change names several times, firstly there was the f2 Summar, then the f2 Summitar, then the various f2 Summicrons. The optical formula did change from Summar to Summicron.

 

[Gabriel M.A.]

Ok, good point; I should reword that: the Summicron would have changed names several times already. I think the Summicron has undergone more "fine tuning" than anything. The change from Summar to Summitar was radical, as well as the change from Summitar to Summitar *, and Summitar * to Summicron.

 

[Doug]

Unlike Biogon and Planar, the Summicron, Summilux, and Elmarit names have more to do with maximum aperture than lens formula. Cosina has been doing something in between, it looks like, with fastest lenses being called Nokton, less fast called Ultron, and more modest apertures are Skopar. But then Heliar pops up both long and short, and Lanthar...

 

[Huck Finn]

According to Erwin Puts, it is historically descended from the Summar & Summitar types - Leitz's early attempts at a high speed (f/2) standard lens. The change with the introduction of the summicron was to increase the diameter for a higher level of correction & reduced vignetting. The Summicron otherwise continued the basic double-Gauss 6-element design type of this family of lenses, which "offers excellent possibilities for aberration reduction." Each generation seems to have its own variations on the optical characteristics of this family.

 

[Hektor]

Leitz lens names were originally quite arbitrary, even called after the designers' pets, but the Summicron contained the 'cron bit to signify the newly introduced lanthanum "crown" (cron) glass. Around the early seventies they decided to unify the names to signify the maximum aperture. However you look at it, and over what periods, they have not, however, been entirely consistent, presumabley - by choice !

 

[Hektor]

Elmar is thought to be Ernst Leittz, - E.L.mar

Elmax - the designer was Max Berek.

 

[Film dino]

I thought "Summicron" denoted designs based on the double Gauss "symmetrical" format- hence "summ---" ?