Archived posting to the Leica Users Group, 2006/11/27
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]The first 5cm/50mm Summicrons were all of a seven element design, though the second variants -- the rigid and the NF/DR -- use a slightly different optical formula as suggested at II Lager 54. These lenses were replaced in 1969 by the six-element Summicron. Most scholars who have studied Leitz/Leica lenses seem to view all of these seven-element lenses as a single type. See, inter alia, Rogliatti 62 - 63, Laney 132, II Lager 166-167, Wright & Glanville 66-67. I am abashed to note that, though I have owned a copy of THE LEICA LENS COMPENDIUM for several years, I have never consulted it on the 2/5cm Summicron. I was therefore surprised to find that my friend Erwin does segregate the collapsible lens as Type I and sets the rigid and DR/NF lenses apart as Type II. I have never seen this done in this way before, though I understand his method. He does identify the distinctions in design between the collapsible and rigid/NF/DR versions, incidentally -- Leica would take to him while spurning many another student of the breed! He also confirms that the DR/NF version is identically optically to the rigid lens, which I had doubted but on which I appreciate being corrected. So, to me, all seven-element 5cm/50mm Summicrons are Type I. To others, they are Type I (collapsible) and Type II (rigid and DR/NF). In any event, my basic point stands: the collapsible lens and the rigid versions are distinct and both have distinct signatures in use. Frankly, I have found the 2/5cm NF to be an absolutely satisfactory lens but, then, I am also quite happy with my Summitar. Marc msmall@aya.yale.edu Cha robh b?s fir gun ghr?s fir!