P3D Ilex Paragon lenses

[John Slivon <frogs@xxxxxxxxxx>]

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>My own experiences with the Paragon lenses mirror your... they are fine
>performers even wide open, best at f/11. They seem to have a bit higher
>("better?") contrast and a more pleasing color cast than the David White
>and many other stereo triplets, probably the result of different/heavier
>lens coatings. And like all Realists (and Reveres, Belplascas) being
>non-front cell focusers means they should have fewer compromises
>optically than some of the other stereo cameras...
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I believe that the Ilex Paragon lenses are tessar type lenses, not simple
triplets (see pages 54 and 55, Photography, its materials and processes by
C.B. Neblette, 5th edition, 1952.) I own an Ilex Paragon f4.5 12" f.l. lens
that fits my 8x10. It is a tessar type (2 element rear lens) and quite
sharp. As per an earlier posting to the list, one of the characteristics of
Tessars and simple Cooke triplets is the ability to change focal lengths of
these lenses by moving the front element. Zeiss used this method on their
Ikonta series cameras. The Ikontas and Super Ikontas use a front element
focusing triplet (Novar) or Tessar. 
Although I have not seen a Realist with Paragon lenses, I suspect that by
looking through the lenses at the aperture plate, you should be able to see
a field wider than the openings in the aperture plate similar to the Realist
2.8. 

John Slivon


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