[LargeFormat] 5x7 Lens Information

[Richard Knoppow]

At 09:46 PM 08/25/2002 +0100, you wrote:
>At 11:16 am -0700 25/8/02, Rich Lahrson wrote:
>>Hi Clive,
>>
>>     Yes, I've been viewing Michael Gudzinowicz's lens page on the f/32
>>forum.  An
>>interesting lens is an older Kodak Wide Field Ektar 190mm/6.3.  The
>>image circle
>>is listed as 318mm. This lens is a definite candidate for purchase.
>>
>>      If anyone has experiences  and other info on this lens, it would be
>>appreciated.
>
>Rich,
>
>The 190mm WF Ektar is certainly a candidate for 5x7, however prices 
>are inflated as it'll just about cover 8x10. Really it is not that 
>good a choice for 8x10 as you end up not being able to use any camera 
>movements and there are other less expensive options for 8x10. I use 
>the 250mm WF Ektar on 8x10 - has a huge image circle and means that 
>you can use movements. Downside is that it is big and heavy (in a #5 
>shutter).
>
>Perhaps some of the lenses used here for 5x7 here may be of interest 
>and all are considerably less expensive than the current going rate 
>for a 190 WF Ektar:
>
>
>135mm Kodak WF Ektar
>165mm Schneider Angulon
>210mm Wollensak Raptar
>300mm Turner Reich Triple Convertible
>450mm Kodak Ektanon
>
>Cheers,
>        Clive
>
  Watch out for Turner-Reich lenses. This is a five element per cell lens
designed by Ernst Gundlach, probably to get around the Zeiss Protar patent.
They are not parcicularlly well corrected lenses. The single sections have
significant color fringing and overall performance of either single cells
or combined lenses is inferior to the Protar. 
  Also, Gundlach's QC was not very good. Many T-R lenses have centering
problems. At least two incarnations of companies made the T-R, the earlier
ones were made in Rochester, N.Y., later ones in Fairport, N.Y. Most of the
Fairport lenses were made to meet a government spec written for the Dagor
or Protar. I would avoid all of them. 
 Ernst Gundlach designed at least three lenses which were essentially
rip-off's of existing patented lenses. The earliest was the Gundlach
Rectigraphic, a three element version of the Rapid Rectilinear, the others
were the T-R and the Gundlach Radar, which is a Tessar with three cemented
elements in the rear. The extra elements in all cases comes mostly from
splitting an element into two rather than any attempt to improve
corrections. I would avoid all of them.
 As far as Zeiss vs: Bausch & Lomb, I suspect but have no proof that the
Zeiss versions were the better of the two although maybe not by much. Zeiss
seems to have had the magic for cementing, most old Zeiss lenses seem to
have intact cement. 
----
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com