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Wollensak 90mm f12.5 Extreme Wide Angle

 
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Alfie



Joined: 13 Oct 2002
Posts: 15
Location: Massachusetts, USA

PostPosted: Sat Nov 29, 2003 5:27 am    Post subject: Reply with quote

Hello all,
Does anyone know if the Wollensak 90mm f12.5 Extreme Wide Angle Raptar is of a different formula, and has different coverage, than the f6.8 Wide Angle Raptars? In "Photographic Lenses" by C.B. Neblette the f6.8 WA Raptar is shown as being the same 4-element formula as the Wide Field Ektar and a host of other WA lenses, while the 159mm f9.5 WA Raptar is shown as an 8-element 4-group lens, like a dialyte composed of cemented doublets (I'm not too up on lens lingo, but I think this is a more-or-less correct explanation). The f12.5 Extreme WA isn't in the book. Basically, I'm wondering if the 90mm f12.5 EWA has greater coverage than the 90mm f6.8 WA Raptar. Does anyone know? Is it suitable for 5x7?
Thanks!
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RichS



Joined: 18 Oct 2001
Posts: 1468
Location: South of Rochester, NY

PostPosted: Sat Nov 29, 2003 5:41 am    Post subject: Reply with quote

My book doesn't give the construction details for the 90 EWA f/12.5 but it does state that it was made for 5x7 coverage if that helps...
The 90mm f/6.8 WA Raptar is listed for 4x5 coverage only. And that may help answer your question.


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Alfie



Joined: 13 Oct 2002
Posts: 15
Location: Massachusetts, USA

PostPosted: Sun Nov 30, 2003 7:02 am    Post subject: Reply with quote

Thanks!
Despite my longwinded question, the 5x7 coverage issue was basicaly all I wanted to know.
Now if I can only find a nice one for a reasonable price...


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rwarhover



Joined: 11 Aug 2002
Posts: 8
Location: New York City

PostPosted: Sat Dec 13, 2003 12:49 pm    Post subject: Reply with quote

I recently bought a Wollensak 159mm f/9.5 which will cover 8x10.The trouble with a lot of these lenses (mine included) is that they were cemented with Canadian Balsom and element separation is common. When I got my lens (eBay) it looked fine at first glance but with magnification you could see hundreds of tiny "bubbles" inside. These are tiny air spaces caused by the separation. The end result is extreme diffusion/halation/softness (obvious on the ground glass). If you buy an old Wollensak, look at it with a loupe or view it on a camera first if you can.
Good luck, Bob
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