I should have added the caveat, Im talking about curved or spherical plane of focus on NON infinity focus subjects. It certainly is going to give you a different projection than a single exposure on a wide angle camera because the back isnt rotating.
Regarding architectual phots with a view camera, the standard method is to keep the film plane parallel to the building front, then NO distortion occurs and you don't need any tilts or swings which could introduce distortion because the entire front will fall into focus if the back is parallel. JCO -----Original Message----- From: William Robb [mailto:[EMAIL PROTECTED] Sent: Wednesday, September 22, 2004 1:32 AM To: [EMAIL PROTECTED] Subject: Re: Large Format vs. Digital/Stitching ----- Original Message ----- From: "John C. O'Connell" Subject: RE: Large Format vs. Digital/Stitching > If you pan the camera to take the sequence of photos > to be stitched later, isnt the fact that the camera > back is panning going to give you a curved "plane" > of focus or in the case of vertical as well as > horizontal panning, give you a spherical "plane" > of focus? > > I would think this could be masked with small apertures > to gain depth of field, but what about geometry? > I don't see how you could do architecture via stitching. Another > thing, in order to get correct geometric projection, wouldn't you need > to mount the camera such that the panning axis is at the nodal point > of the lens instead of the usual tripod mount which > is further back near the focal plane? Depth of field isn't going to be much of a problem, in fact it may well be less of a problem than with the view camera, since you can refocus for each exposure, rather than depending on camera movements or lens depth of field primarily. I can't really see too much of a problem shooting architecture, but I also haven't tried this technique for it, so I don't know if anything unsurmountable would crop up. Obvioulsly, one would be doing some work in Photoshop to correct the perspective. Not ideal, but certainly doable, and I expect easier with a view camera, all else being equal. Sometimes all else isn't equal...... I was hired once to shoot an office building. The AD wanted some street detail, but also wanted the building to look "strong" (her descriptive, not mine). What I settled on was to overcorrect the verticals, so that the building would actually be "leaning in". My test shots (not of the building in question, it was in a different city, so I picked a local office building of similar height to test my idea) were accepted as a good idea, and I was hired. Unfortunately, there wasn't any way to do the shot in camera. In order to get wide enough to fit the entire building in, the bellows was so short that I couldn't fully correct the vertical, much less overcorrect it. Today, I would "fix it in Photoshop". My option in 1986 was to do some massive whacky easle adjustments in the darkroom. Having the pivot point at the nodal point is technically the best way to do it, but I think with digital stitching it will be less of an issue. It really depends on scene type, most scenes are very forgiving, some are not. The typical methods for gaining depth of field with a view camera have potential for causing massive amounts of image distortion, but ususally it doesn't seem to matter all that much. William Robb
