[LargeFormat] Wide field and Commercial Ektars

[Richard Knoppow]

----- Original Message ----- 
From: "Georges Giralt" <georges.giralt at free.fr>
To: "f32 Large Format Photography Mail List" 
<largeformat at f32.net>
Sent: Tuesday, August 09, 2005 12:38 PM
Subject: Re: [LargeFormat] Wide field and Commercial Ektars


> Les Newcomer a écrit :
>> Does anybody have an introduction date or "earliest 
>> known" date for these lenses in any focal length? The 
>> best I can get is a 1948 edition of "Kodak Lenses"  which 
>> mentions them, but doesn't say they are new or just 
>> introduced.
>>
>> While I'm asking for dates, when did the Copal shutters 
>> start coming into the US market?
>>
>> Les
> Hi Les !
> I've just checked a French book of 1947 vintage.
> My thought is that Kodak (and many others ) had a boost 
> using the knowledge German people had, and get as a 
> reward, the know how to improve some "well known" optics 
> gained by the Zeiss, and Schneider.
> In my book, the "new " (in 1947 ) optics from SOM, Boyer 
> and al are copycats of pre war Schneider or Zeiss optics.
> My opinion is that Kodak, and to a lesser extent the 
> Japanese get access to the very same information  French 
> and Great Britain opticists had at the end of the war when 
> people could go into the German optics secrets... Be it 
> glass making secret or technical knowledge in centering or 
> polishing the lenses...
> I remember my grand father telling me he has seen coated 
> German optics _before_ WWII. When had Kodak (and others) 
> begun to coat their optics ???
> Of course, this is just a thought, so I may be wrong... 
> Don't take it for granted ;-) I was not born at that time 
> ....
> -- 

     Kodak was making outstanding lenses before any access 
to German design "secrets" became available after WW-2. 
There were not many secrets to begin with. Zeiss was the 
outstanding optics company in developing modern optics but a 
great many innovations and improvements came from elsewhere, 
for instance, Kodak and Taylor, Taylor, and Hobson. 
Schneider was not a maker of quality optics until after 
WW-2.
     While the original design for the Planar type lens was 
invented by Paul Rudolph, of Zeiss, his design was not a 
very practical one. The first semi-symmetrical version of 
this lens was the Opic, of TT&H, designed by Horace W. Lee 
in the late 1920's. The better known Zeiss Biotar was a 
later lens.
     The secrets of making optical glass were solved in the 
US during WW-1. Bausch & Lomb began making glass on a small 
scale in 1912. This formed a basis from which a national 
effort stemmed during the war. By the end of the war at 
least five companies in the US were making large quantities 
of glass equal in quality to that from Schott. Rare earth 
glass was developed at the United States Bureau of Standards 
and commercialized at Kodak. The first lens using Lanthanum 
glass was the first Ektar, built for a Kodak 35mm camera.
   While vacuum coating was evidently begun at Zeiss c.1935 
the technique was known and was developed much further in 
the US, again by a co-operative effort during WW-2. It was 
here that the technique of baking the coatings in the vacuum 
chamber, rather than later, was developed. The advantage of 
this technique is that the bond between the coating and 
glass is much stronger than if the coating is baked in air 
later or not baked at all.
   Kodak always made good lenses but their lenses became 
outstanding after Rudolf Kingslake became manager of the 
optical department about 1939.
   Most basic lens designs for simpler lenses were worked 
out by the mid 1920s and most date from well before that. A 
very few designs date from later. The Roosinov lens, the 
basis for most modern wide angle lenses are based on 
Roosinov's design, c.1948.
   I don't know as much about the French optical industry as 
I would like. France was well known as a pioneering country 
in optics in the nineteenth century. Both France and England 
had well established optical glass factories by the turn of 
the last century. There is more but the point is that not 
all invention and innovation in optics came from Germany.

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