Archived posting to the Leica Users Group, 2003/08/26

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

Subject: Re: [Leica] Re: Re: Leica 90mm f/4.0 Elmar C prices
From: Marc James Small <msmall@infionline.net>
Date: Tue, 26 Aug 2003 21:28:26 -0400
References: <1e1.eff10f1.2c7d4e6a@aol.com> <1e1.eff10f1.2c7d4e6a@aol.com>

At 05:50 PM 8/26/03 -0700, Henning Wulff wrote:
>
>Many longer, slower Nikon lenses have f/32. The problem with f/32 on 
>the 90 is that while the depth of field may be large, diffraction at 
>that aperture is severe enough to make everything medium fuzzy. Not 
>an effect one aims for with Leica glass.

Henning

A MOST excellent point.  Note how many of the Leitz and Contax lenses made
before the War stop down only to f/8 or f/9 or so, as the manufacturers
were concerned over diffraction degradation beyond that point.  (The Zeiss
Jena 1.5/5cm Sonnar, for instance, went from f/8, f/11, f/16, and then f/22
between 1937 and 1945, as the effects of coating were confirmed to combat
diffraction effects.  My oldest of these lenses is a quite early coated
one, but only stops to f/11.)

Marc

msmall@infionline.net  FAX:  +540/343-7315
Cha robh bąs fir gun ghrąs fir!

- --
To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html

In reply to: Message from Afterswift@aol.com (Re: [Leica] Re: Re: Leica 90mm f/4.0 Elmar C prices)
Message from Afterswift@aol.com (Re: [Leica] Re: Re: Leica 90mm f/4.0 Elmar C prices)