Chris, I believe that the Super Angulon 72mm XL does have an image circle approa ching 259mm, or at least pretty close. Alan has one, he could probably verify t his.
Perhaps LF lens designers could come up with a 58mm XL or a 47mm XL with a large r image circles than 166mm; a new line of XXL's? Schneider and Rodenstock have been offering shorter lenses with larger and larger image circles in recent yea rs. I think that trend is great; they shoud keep on pushing the envelope.
The cost might be prohibitive, though. And I question whether the demand (or ne ed) for such lenses would justify the high design and manufacturing costs. I'm not a lens designer, but I would think that at some point certain design limits will be reached.
But, as it stands now, these lenses (45mm, 47mm, 58mm) provide a marginal usable image circle for 4x5. That makes them more difficult to use well. It is very easy to displace such a small image circle. That is why most people would advis e against getting one of these as your first WA lens.
These ultra-wides do work particularly well for interior architecture, particula rly in tight, cramped situations, precisely because they are often focused at di stances much closer than infinity, increasing their usable image circle. This g reater bellows extension, and the resulting increase in usable image circle, wil l allow for greater movements in situations when they are most needed.
I believe Alan is correct--the longer the focal length for a given format, the g reater the need for larger image circles to allow for movements. For a variety o f reasons, the degree of Scheimpflug tilts/swings necessary with wide angle lens es is much less than with longer lenses.
I believe this would also hold true for shift movements. (You know, I cannot rec all the last time I actually used a shift movement with a WA lens.) Your plaus ible theory that greater shift movements might be necessary with WA lenses, part icularly when the lens is positioned closer to a subject, would probably be offs et by the very substantial decrease in magnification with WA lenses, when compar ed to longer lenses.
Have you noticed how very tiny things look on a 4x5 groundglass with a 58mm WA? I would not take much of a shift with a 58mm to achieve the desired effect, no matter how close the subject.
Keep up the questioning attitude. Take care. Sergio.
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