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Old Nov 16, 2006, 1:29 AM   #1
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I'm playing with the software that came with my new Canon.

PhotoStitch did an OK job with the 180-degree series I took with the A540's Stitch Assist, offhand. I had too much distortion from too wide an angle, and between that and some misalignment, it had a rought spot.

A 400-degree that I took offhand with a point-and-shoot film camera came out OK after I removed the overlap.

But my favorite panorama it couldn't handle. I took 32 shots inportrait orientationwith an old Canon FtB with a Vivitar 35-105mm lens (at 105mm) in 1985 from the top of a high-rise building. I did an amazingly good joblining the metering-area rectangle in the viewfinder with the horizon. I had to take the series in two halves, because I could only get on top of the elevator penthouse, not on top of a water tank, and thereare some parallax issues with the roof of the building I was on where I shifted positions that can't be completely fixed.

I used to have the prints scotch-taped together and on various office walls, all 10 feet of them. I had a new set printed and scanned them around 2000, and used one of the most expensive pieces of software I've ever bought to stitch them, PhotoVista which was then produced by Live Photo (later it was produced by I See Media.) I've got various versions of the resut here. (Today IE found the zoom viewer to view the .IVR file, but it doesn't seem to work for me.)

I figured modern software has got to be that much better (and I ought to retouch out the seams and some color casts), so I let PhotoStitch loose on the scans. No matter what I did, it merged about 6 shots, and then started skewing them off at about a 30 degree angle, and after one or two more it just gave up. Is there some way to tweak PhotoStitch so it can understand this series? I would like to be able to use its "save as a QuickTime movie" feature. The horizon is a pretty strong matching feature, there's not much distortion at 105mm, and most of the pairs have just the right amount of overlap.
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Old Nov 18, 2006, 12:43 AM   #2
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My guesses are
(a) there is insufficient overlap as they were originally shot to butt up to each other with no or little overlap.
(b) something else is getting the software confused.

Can you post a couple of the ones which should overlap but don't?

Do you have autostitch from here?

http://www.cs.ubc.ca/~mbrown/autostitch/autostitch.html

It is a demo of new techniques that has been sold to other software companies. If it can't alighn the images I don't think anything will.
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Old Nov 21, 2006, 11:20 PM   #3
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Autostitch seems to have lots of intelligence in it, but it got confused with some shots I took with the Canon A540 in stitch-assist, attached if I can figure out how. For the older shops there is a pair with minimal or no overlap, though butting them together would work.

If I'm going to attach these one at a time, here is the left of the non-matchable pair in the old set:
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Old Nov 21, 2006, 11:21 PM   #4
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Here is the right of the unmatchable pair from the old set
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Old Nov 21, 2006, 11:57 PM   #5
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Here are the two shots from the new set that could not be matched by Autostitch, butted together using Irfanview, on the top half of the image, and details from them in the bottom half.

The repeated patterns (pillars, heads) must make this a difficult problem, but the text of the years makes the overlap clear, and the sky/banner/stadium should make alignment easy.

Because the photographer was at the bowl end, the elements at the right of the desired panorama are much bigger than comparable elements at the left, but it is all properly gradual. (The photographer, Class of 1983, was seated behind members of the Class of 1982, whose major, 25th, reunion is coming up later this academic year. Having never lettered in a sport, it's going to take a 6-figure donation for the photographer to ever get seats near a numbered yard line.)


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Old Nov 22, 2006, 12:12 AM   #6
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At first glance it seems that Canon's PhotoStitch does a great job stitching six shots together (the attachment is 1/5 size and 75% JPEG quality, post-processing the PhotoStitch output with IrfanView)...
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Old Nov 22, 2006, 12:13 AM   #7
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But in reality it merely punted on the seam that AutoStitch refused:
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Old Nov 22, 2006, 12:23 AM   #8
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And besides, it's a dumb idea to try to make this into a panorama. There aren't enough clues for the eye to realize it is seeing half a horseshoe. A 360, taken from midfield, and viewed as quicktime or some sort of VR would work nicely.

Update: Given how AutoStitch can handle 2-dimensional mosaics, maybe in two years I'll try this again with another row showing where the stadium meets the field.
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Old Nov 22, 2006, 1:13 AM   #9
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As suspected 12 and 13 have no overlap which all stitching progs require. Canon Photostitch is not bad but is a 'beginners' prog and needs well matched images to work. Probably best to use a tripod (where you can) to get more accuracy.

Bill
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Old Nov 22, 2006, 3:25 AM   #10
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The problem with Photostitch's bad seam is easy to deal with. You just need tohelp
Photostitch along by identifying matching features in the two images. Click on Edit
Seamsand then click on the seam you want to edit.
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