Archived posting to the Leica Users Group, 1997/06/12

[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]

Subject: Re: Noncoated filter
From: Marc James Small <msmall@roanoke.infi.net>
Date: Thu, 12 Jun 1997 13:01:20 -0400

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!