Re: [Leica] Summicron 50 mm question

[aglang@sprynet.com]

C'mon Erwin, just look at the two lenses (collapsible and rigid) . Set both on a 
flat surface locked at infinity. The front elements differ by a couple of 
millimeters in their height. Quod erat demonstrandum. Furthermore Mandler 
himself obliquly referred to the difference in an article in Viewfinder (LHSA) 
on early use of the computer (1989? ask Marc Small for the precise reference, he 
has noted it here before)at Leitz for lens design. The computer was used to 
recalculate the formula of the Summicron for the rigid version. I do not 
understand your reference to the 1954 brochure since the rigid design was not 
released until several years later. To my knowledge Leitz never acknowledged the 
change, but that doesn,t prove anything, how long did it take them to announce 
the optical formula change change of the RF 50 Summilux??!?

On Wed, 28 Jan 1998, Erwin Puts <imxputs@knoware.nl> wrote:
>>Dave,
>>Increase your version number by one, ie the current optical design is
>>v 4, since the original collapsible and firest rigid chrome lenses are
>>distinct
>>optical designs....
>
>This statement has been made several times and has never been proved. The
>original Leica brochure from 1954, describing the introduction of the
>Summicron, including its optical properties, show the identical design for
>both versions. My own findings support the conclusion that the collapsible,
>the rigid and the DR are optically identical. Unless somebody gives really
>factual and conclusive evidence to the contrary, I would prefer to state
>that there were inly three designs and the current one is number 3 and not
>number 4.
>Erwin
>
>