Archived posting to the Leica Users Group, 1993/04/23
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Date: Thu, 22 Apr 1993 08:01:45 -0400 From: Jeffrey Frey <jeff@eng.umd.edu> How can I tell whether my 50/2 Summicron (Screw-mount) has 6 or 7 elements (or is it 7 or 8?)? If you have the answer, where did you find it? According to van Hasbroeck (Leica -- A History Illustrating Every Model and Accessory), the 50mm Summicron is a modified 7-element Gauss computation. He also notes that it was recomputed with 6 elements in 1971, with focusing to 0.7 meters. However, if yours is the screw-mount model, you don't have this one. Also, Morgan (Leica Manual and Data Book, 14th edition, 1961) has a cross section of the 50mm Summicron which shows 7 elements in 6 groups. Aaron P.S. Does it happen to be the rigid model? Only 1000 of those were made. -- Aaron Heller, EK264 Internet: heller@ai.sri.com SRI International Phone: 415/859-2618 333 Ravenswood Ave. Fax: 415/859-3735 Menlo Park, CA 94025