chauncey wrote in post #9134688
With all due respect to those that have already responded...you don't have the op's difficulties if you take multiple images with a longer lens and photomerge them.
Sure you do. The back of the camera still has to be vertical, or you have to distort the image in software (which is what Photomerge does). You could also take the images he made and correct the perspective using something like Panotools (or even the perspective envelope transformation in Photoshop), but again there would be a lot of pixel interpolation going on.
And it isn't that easy. I have found that Photomerge basically sucks at aligning images. In this image...

...I had a single, 6x12 transparency made in one exposure using an ultra-wide lens in my view camera. My Nikon film scanner only scans up to 6x9, however, so I scanned this as two 6x7 images with plenty of overlap. The two scans were absolutely identical in scanner parameters, and since they came from the same exposure, they were identical in the overlapped areas down to the pixel. But when I tried to merge them with Photomerge, I found that it missed by a very large margin in aligning the images, and I had to do it manually (not easy with a file that ended up with about 57 megapixels).
And I had to manually go in and set merge points when putting these nine images together. It was worth the trouble, but it took many hours to get it right. With these, the trees still needed to be vertical, so I carefully leveled the camera to eliminate vertical perspective convergence. But horizontal perspective was handled by the cylindrical panoramic projection, though that required LOTS of pixel interpolation.
These tools seem to have been designed for images for web display--at web resolutions the automatic merges were acceptable. But for large prints, a miss is as good as a mile, and they missed (or I didn't know how to use them, despite following instructions from experts carefully).
Rick "not to mention the problem of blending clouds that moved between exposures" Denney