Archived posting to the Leica Users Group, 1997/06/12
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]At 09:32 AM 6/12/97 -0700, you wrote: >I have an old Summitar (SM 5cm F2) which is coated on each surface EXCEPT the >front. It is sufficiently late to have been factory coated. I guess the front >coating got damaged and was ground off. Lens is still quite good (except very >stiff aperture ring) and I had assumed that the only real detriment was a loss >of effective spped due to reflection back into the environment from the front >element (as opposed to an internal uncoated surface creating more reflections >bouncing around and ultimately decreasing contrast on the film). It was common practice prior to 1955 or so to only coat the internal elements, though I believe Leitz coated all surfaces on their lenses. Marc msmall@roanoke.infi.net FAX: +540/343-7315 Cha robh bas fir gun ghras fir!