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Linas Kudzma
4-Nov-2001, 08:59
Hello folks, Anyone know from personal experience if a 480 mm Ronar would cover 8x20 inches s topped way down? Shooting at f90 (or smaller) won?t be a problem, I already do t his with 8x10 and contact print in Pd/Pt. Any diffraction issues are a non-probl em to my eye. The exact lens in question is a barrel Rodenstock-chemco-Apo-Ronar 1:9 f=480/19in. serial# 5 982 151. I was told this lens came from a scrapped ne wspaper copy camera. I don?t know what the ?chemco? indicates, I?m assuming the lens is the same design as a ?normal? APO Ronar. Is this correct?

I?m hoping to use this lens with an as yet unfinished homebuilt 8x20 camera. I?l l answer my own coverage question eventually, however was wondering?.

Alexander Selzer
4-Nov-2001, 09:54
Hi!

I would say no. You will need an image circle of about 547mm. Stopped down to k= 22 and at inv. the Apo-Ronar has 396mm (see http://www.rodenstockoptics.de/roden stockoptics/standard_products/photo_optics/prof_phot_lenses/apo_ronar_data2.htm) . But at a scale of about 1:4 (AFAIK) it could be enough. But I don't think you wi ll do panoramas with that short working distance.

Alex

Linas Kudzma
4-Nov-2001, 14:43
Alex,

Thanks for the answer and the Rodenstock link. The 46-degree angle stated in that link confirms what I?ve seen elsewhere. The thing that confuses me is that 19? Atars are reputed to cover 8x20 but have the same angle. The Atars shouldn?t cover, but supposedly do. Do they?

Is it true that the APO Ronar and Atars are a similar optical design?

Pete Andrews
5-Nov-2001, 02:14
If you're not going to break the bank on this one, you really want a wide coverage process lens like an Apo-Gerogon, or G-Claron, with 70 degrees angle of view.Another good wide-angle process lens is the Konica Hexanon GR-II, which appears to me to cover over 75 degrees, but they're HUGE bits of glass, and not too easy to find.

Alexander Selzer
5-Nov-2001, 11:46
Linas,

sorry, but I don't know the Atar lenses.

Alex

Ed Burlew
5-Nov-2001, 17:12
This is not the exact answer but get a 600mmm fuji , It will cover and is very very sharp.

Linas Kudzma
6-Nov-2001, 06:26
Thanks to all who have answered! In fact, I do have a lens that I know will cover 8x20 (14? Dagor). I was specifically interested in the limits of coverage with the 480 Ronar from anyone with >personal experience<. I love the Ronar on my 8x10, it?s an amazingly sharp and contrasty lens even stopped way down to f90 and even f128 (I contact print so I get away with such stuff). As for the Fuji lens recommendation, I?m sure you are right. I have several Fuji lenses for 4x5 and they are fantastic. I saw the Fuji 600 this weekend at PhotoPlus in NYC on a Wisner built monster sized Polaroid camera. That 600mm lens is one big hunk of glass!!

Linas Kudzma
3-Dec-2001, 10:14
Update: For anyone that might be interested, my homebrew 8x20 camera back is built and this particular 480 Ronar (details above) does indeed cover 8x20" at small f-stops focused to about 50 feet or so. All published specs seemed to imply that it would not cover, but it does.

Linas Kudzma
12-Mar-2002, 11:44
Update #2: I've rebuilt my 8x20 camera and now don't have the small bit of bellows vignetting I had in my previous set up. Turns out that the 480mm Ronar just misses full coverage of 8x20. Even at f90 the very corners are a touch soft. While still usable for 8x20, my particular 480mm Ronar does not fully cover with the beautiful sharpness of the central image.