I'm fairly new to lf so just to say thanks for this forum, it really helps. Does anyone out there know the coverage of a rodenstock 120mm 5.6 sironar N circa 1989 I think. I've just got my hands on it and tried the usual web sites that you recommend but without success.

-- dave bulmer (dave.bulmer@bl.uk), September 20, 2000

Answers

Where's Bob Soloman when you need him??? Bob probably dreams about this kind of stuff. Contact HP Marketing, they have a web site and are the US distibutor for Rodenstock. This is a falling-off-a-log easy question for the Bobster.

-- steve (s.swinehart@worldnet.att.net), September 20, 2000.

OK. A few questions further down is one on Linhof equipment that Bob answered. His email is: bobsalomon@mindspring.com). Now, if Bob doesn't get to your question, just email him and I'm sure he will answer your question.

-- steve (s.swinehart@worldnet.att.net), September 20, 2000.

Further down is a question on Rodenstock Imagon lenses. Bob is going to Photokina and won't be back until 10/2. So, I'd suggest emailing him and waiting for the answer.

-- (s.swinehart@worldnet.att.net), September 20, 2000.

Dave: Are you sure? I have Rodenstock literature from 82, 87 and 93 and none of it lists a 120mm Sironar-N?

-- Glenn C. Kroeger (gkroeger@trinity.edu), September 20, 2000.

I believe that the N suffix was added when the Apo Sironar, and other varieties of Sironar were introduced. Before that, it was just plain Sironar. If you find the coverage of any of the other focal lengths of 'plain-jane' Sironar or Sironar-N, then you can just scale the coverage circle down.
At a guess, it's going to have a circle of about 180mm at f/22. It'll just about cover 5x4 with no movements.

-- Pete Andrews (p.l.andrews@bham.ac.uk), September 21, 2000.

Thanks for the info. I noticed on another thread that Bob had given a mauling to someone new, like myself, who had asked an "easy" question, so perhaps its as well that he's not around at the moment. Only joking folks. Appreciate your time.

-- dave bulmer (dave.bulmer@bl.uk), September 21, 2000.

Dave, Pete: The N appeared before the Apo! The '82 literature lists Sironar-Ns, but Apo-Sironars appear in '93. As I recall, the Sironar- N was a slight redesign that appeared about the same time as the Symmar-S (as opposed to the Symmar)

-- Glenn C. Kroeger (gkroeger@trinity.edu), September 21, 2000.

OK Glenn, I stand corrected. Why not tell us the coverage of a 150mm Sironar-N and we can divide it by 5/4.

-- Pete Andrews (p.l.andrews@bham.ac.uk), September 21, 2000.

I have an old Rodenstock brochure which appears to be from Jan 1991 (guessing that 1/91 on the back page is the date code). The 120 mm f5.6 Sironar-N is listed as having an image circle diameter of 175 mm at f22. This implies allowable shifts of 13 and 17 mm on 4x5 or 20 and 25 mm on 9x12 cm film (since the question comes from the UK).

All of the Sironar-N's from 100 mm to 300 mm focal length have 72 degree coverage, so one can calculate the image circle diameters. The 360 mm has 64 degrees and the 480 mm 56 degrees.

-- Michael Briggs (MichaelBriggs@earthlink.net), September 21, 2000.

Thanks Michael... now we don't have to do any math! That lens must have been produced for a short time between '83 and '93. Having used a 120mm Apo-Symmar with a 179mm image circle, I can say that although tight on 4x5, it can be done if you are willing to use mostly back movements. If the Sironar-N is like the Apo-Symmar, the actual image circle is a bit larger than the specs indicate. At f/22, I measured mine to be 184mm.

-- Glenn C. Kroeger (gkroeger@trinity.edu), September 21, 2000.

Just what I needed to know. Thanks again to all who contributed.

-- dave bulmer (dave.bulmer@bl.uk), September 22, 2000.