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Author Topic: Genesis of a Lens Hood...  (Read 630 times)
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sandeha
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« Reply #15 on: September 10, 2010, 12:32:42 PM »

Yup, that'll be the lens design then.  The why of their inventing centre spot filters for WA lenses, though I wasn't aware of them being necessary for a 90mm.

Just checked - there's no darkening on the corners of my 90mm Angulon negatives, though I've always shot at f16 or f22. 
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sandeha
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« Reply #16 on: September 11, 2010, 05:14:20 AM »

Lens coverage means different things to different people so concrete data will be hard to find.  However, if the image circle of the 90mm Angulon is just over 125mm the Optar may be slightly less.

http://www.largeformatphotography.info/forum/showthread.php?t=14915

That may be where the vignette is coming from.
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Madrigal
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« Reply #17 on: September 11, 2010, 06:22:46 AM »

Awesome. Nice work on the lens hood. I should make one of these.
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Character, like a photograph, develops in darkness. -Yousuf Karsh
Scott
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« Reply #18 on: September 11, 2010, 10:06:58 AM »

Lens coverage means different things to different people so concrete data will be hard to find.  However, if the image circle of the 90mm Angulon is just over 125mm the Optar may be slightly less.

http://www.largeformatphotography.info/forum/showthread.php?t=14915

That may be where the vignette is coming from.

Well, that stinks.
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