Archived posting to the Leica Users Group, 1997/07/29
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]This is a MIME message. If you are reading this text, you may want to consider changing to a mail reader or gateway that understands how to properly handle MIME multipart messages. - --=_673587B7.E382EFE3 Content-Type: text/plain Content-Disposition: inline Be aware, The "yellowish" tint in the coating can easily be mistaken for the discoloration of radioactive glass. Some, and I mean only a few of the early 50mm Summicrons used a "rare earth" glass that was truly radio active. Not enough that would fog the film or harm someone, but enough that after 40 + years, they are getting that yellowish hue or patina. BTW, If you want a warmer than normal photo, these beauties will do it for you. There has been some interesting articles on this subject with in the last year or so in the LHSA journal. Dave Stedman - --=_673587B7.E382EFE3 Content-Type: message/rfc822 Received: From [149.59.14.23] purg.atl.com By corp.atl.com (GroupWise SMTP/MIME daemon 4.11) Tue, 29 Jul 97 12:52:22 PDT Received: from mail1.halcyon.com (mail1.halcyon.com [206.63.63.40]) by atl.com (8.8.5/8.8.5) with ESMTP id MAA11227 for <dstedm@corp.atl.com>; Tue, 29 Jul 1997 12:52:20 -0700 (PDT) Received: from smtp2.nwnexus.com (smtp2.nwnexus.com [198.137.231.18]) by mail1.halcyon.com (8.8.5/8.8.5) with ESMTP id MAA01476 for <dstedm@mail.halcyon.com>; Tue, 29 Jul 1997 12:52:58 -0700 (PDT) Received: from mejac.palo-alto.ca.us (mejac.palo-alto.ca.us [192.147.236.1]) by smtp2.nwnexus.com (8.8.5/8.8.5) with ESMTP id MAA13629 for <dstedm@halcyon.com>; Tue, 29 Jul 1997 12:51:26 -0700 Received: by mejac.palo-alto.ca.us id AA02462; Tue, 29 Jul 97 12:01:07 -0700 Received: by mejac.palo-alto.ca.us id AA02456; Tue, 29 Jul 97 12:01:03 -0700 Received: (from root@localhost) by emout10.mail.aol.com (8.7.6/8.7.3/AOL-2.0.0) id PAA22090 for leica-users@mejac.palo-alto.ca.us; Tue, 29 Jul 1997 15:02:52 -0400 (EDT) Message-Id: <970729150207_-21698072@emout10.mail.aol.com> Sender: owner-leica-users@mejac.palo-alto.ca.us Precedence: bulk Reply-To: leica-users@mejac.palo-alto.ca.us Date: Tue, 29 Jul 1997 12:02:52 -0700 From: <leica-users@mejac.palo-alto.ca.us> To: Leikon35@aol.com, leica-users@mejac.palo-alto.ca.us Subject: Re: Collapsible Summicron 50 (M3 D/S) Mime-Version: 1.0 Content-Type: text/plain Content-Disposition: inline The softness was in the coating , not the glass. Soft coating usually had a yellowish tint where-as the harder magnesium flouride was more magenta. Re-polishing & re-coating early Summicron lenses comprise a large part of John Van Stelton's work. He does an excellent job for about $100. - --=_673587B7.E382EFE3--