[largeformat] Introduction of 10" WF Ektar

[Richard Knoppow]

----- Original Message ----- 
From: "Les Newcomer" <LNPhoto at twmi.rr.com>
To: "f32" <largeformat at f32.net>
Sent: Saturday, October 01, 2005 2:58 PM
Subject: [largeformat] Introduction of 10" WF Ektar


> I've been trying to find out when the 10" WF Ektar was 
> announced to the world.   I always thought it was a 
> by-product of the WWII Metrogon,  with early intro in '46 
> and wide distribution in '47. (at least that's true with 
> the 135 and the 80mm and always assumed that the whole 
> series came out pretty much together or within a year of 
> each other)  but a friend just pointed out to me that 
> Ansel's picture of Steichen? Steigliz? in a tree, is 
> labeled as shot with a 10" WF  Ektar in 1940.
>
> Could Ansel have shot with an experimental lens?  or worse 
> yet for my theory, a production lens?
>
> Les Newcomer
>
   I think the info on the photograph is wrong. The first 
Wide Field Ektar shows up in Kodak literature c.1947, it 
does not appear in the 1946 reprint of the earlier lens 
booklet. This booklet still lists the Eastman Ektar, the 
soft coated version of the Commercial Ektar. The full range 
of W.F.Ektars is in the 1948 printing.
   The patent for the W.F.Ektar appears to be USP 2,158,719 
filed in 1946 and issued in 1950 to Max Reiss. This shows 
three examples of four element Double Gauss lenses with 
aperture of f/6.3 and half angle of 40 degrees. It is very 
unlikely that any prototypes would have been made available 
before the patent was applied for.
   The Metrogon is a design by Wilbur Rayton of Bausch & 
Lomb, an improvement on the Zeiss Topogon of Robert Richter. 
Both are also based on the double Gauss lens but this lens 
type was very widely used long before either of these aerial 
survey lenses. The earliest photographic lens based on the 
Gause telescope objective was designed by Alvin Clark about 
1888 and built by Bausch & Lomb for a time.  Other, and more 
successful designs based on the double Gauss were the Hugo 
Meyer Aristostigmat, Ross Homocentric, Busch Omnar, all sold 
as wide angle lenses, and many more.
  Again, I think the caption is incorrect (happens all the 
time because such material is written by people who have no 
idea of history. They will accept pictures of Lincoln making 
a phone call, etc).

---
Richard Knoppow
Los Angeles, CA, USA
dickburk at ix.netcom.com