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Old Nov 27, 2006, 4:11 PM   #1
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In the center of my city is a classic New England town common, a little green in the center, a Spanish-American War statue and other memorials, and all around it City Hall, a bunch of churches, and so forth.

The green is a circle, but the current configuration has it surrounded by a triangle representing the three major traffic flows. From ground level inside the circle the WWII memorial wall blocks a key view.

I might try climbing ontoits pedestal and working around the Spanish-American War soldier.

I tried walking around the triangle and shooting outwards on a radius from the statue. It didn't work very well.

Since the buildings around the Common are so close, the different radius made a difference, and there was a significant parallax problem with sidewalk trees and such. Could this be compensated with zooming?

I missed a spot, and as I mused, I created a fake shot bridging the gap. The Canon stitcher still complains since it relies so much on the Exif data. Even with lots of overlap most other places, Autostitch only accepted about 60 degrees worth as belonging to the panorama.

I also have Cool360 -- it came with PhotoImpact 10. It complained about resources, but after a reboot it did complete the circular view. Unfortunately it cropped way too much off the bottom (I shot in portrait orientation, and wanted some street and sidewalk in the picture) so the result is not what I want.

My hand-cum-lens-hood got into the frame on a couple of the south-facing shots. Notsure how best to deal with that. At this time of year, even near noon the sun is getting into the lens without some shading. But I used PhotoImpact to paint over my hand with sky blue, and with all the merges that wasn't a problem.

I'd like to take a picture of the Common as the outside of a cylinder, looking in. How can this be done when the "cylinder" is transparent in places? That is, the parallax between landmarks ON the common and landmarks 100 yards away (the Spanish-American War statue, and a church steeple down the block) make it a nightmare. I suppose I could manually paint over everything on the top half that is "behind" the Common as sky. Do any of the stitchers/viewers deal well with the warpage for an inward looking panorama?
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Old Nov 27, 2006, 6:46 PM   #2
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keep trying while paying attention to where the stitch lines go. A tree trunk, lamp post, or some other nondescript vertical feature is a great place for the stitch line. That means using software that allows you to specify where that is. Having the output in PhotoShop masked layers does the trick - just change the masking to have the stitch line land on asign post.

Make sure that the real problem areas do not land on frame boundries unless anavoidable. You will come to recognize the problem areas if you keep trying to shoot the pano.

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I really don't understand what you mean by "outside looking in":

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...I'd like to take a picture of the Common as the outside of a cylinder, looking in. How can this be done when the "cylinder" is transparent in places? That is, the parallax between landmarks ON the common and landmarks 100 yards away (the Spanish-American War statue, and a church steeple down the block) make it a nightmare. I suppose I could manually paint over everything on the top half that is "behind" the Common as sky. Do any of the stitchers/viewers deal well with the warpage for an inward looking panorama?
By "warpage" I assume you mean projection distortion. That is an unavoidable issue whenever the surface of a shere is projected onto a flat surface. You have a large number of choices of distortion, but there will always be something distorted.
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Old Nov 27, 2006, 7:36 PM   #3
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By "outside looking in" I mean when I'm south of the Common I face north and see the Common, then I take a step to my right and I'm on the south-east of it (east-by-south unless it's a very big step) and I turn leftward until I'm facing northwest, and so forth.

Instead of being in the center of the circle, or walking around the outside of a small circle (or in this difficult case a larger, irregular circle) and when I'm on the north of the circle I face north and photograph to the horizon, etc.
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Old Nov 28, 2006, 9:55 AM   #4
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I doubt you will be able to make a seamless pano of the kind you are thinking of without a serious amount of work. As you noted, parallax issues are really large. More work than I would be willing to do, but you might give it a try.

Another aproach is to not even try to make a seamless 360 degree image. Just put each up as a separate picture: perhaps touching, perhaps framed separately. Looks likethree ~120 degree panos might do the job, or perhaps two 140 degree andone 80 degree.
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Old Nov 28, 2006, 10:45 AM   #5
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I have confused two issues.

First problem, the usual suitable-for-VR pan, complicated by the triangular path.

And like you said, some sort of triptych might capture it well. (The problem is mathematically solvable, because all the information is present in a full set of outward-looking, overlapping views, but it is difficult, even if the photographer was very careful to always shoot exactly.) The three composites would each be of the linear, slide (translate) keeping the camera parallel throughout each side. Canon's PhotoStitch explicitly allows this kind of stitching.

If I were trying to assure a radial shooting direction, I'm thinking that I could attach a ruler or pool cue to the camera, so that I can site backwards at the central landmark, so that no matter where I am on the circumference, I'm pointing in the right direction. (That's going back to the original 360 attempt.) Eyeballing it wasn't enough on that first attempt, but that was a practice run for a lot of reasons.

If I go with the triptych, I can continue on Main Street north and south of the rotary around the Common. That would be useful because the old downtown business district is the few blocks going north. (Similarly the library and district court are on Pleasant St going west.) The seams between the three pieces would be the view to the horizon down the major streets.

The second problem is how to capture the outside of something. If the thing is opaque and circular it wouldn't be difficult: each frame shows one segment. But if the thing is transparent, then parallax comes in. I might be able to handle this by aiming low, so that I never have what is beyond (on the other side of) what I'm shooting in the shot. Here again it might be more useful to follow your suggestion, and shoot the three straight sides, keeping the heading parallel throughout each side.

(An opaque example of this second type is any flat projection of the globe. These can usually be rolled, ink side out, so that the left and right margins meet. The more usual type that we photograph is more like a star map of the celestial heavens, which is right-side-out when the ink is facing in. The only difference is the natural orientation of the subject matter: once it's reduced to photographs it is flat, and whetherthe original subjectis concave or convex to the observer is lost. I suppose that means the warpage or distortion due to projection onto the flat surface of a cylinder, in making the panorama, is the same for concave or convex.)

Except for the earth itself, are there examples out there of panoramic photographs of the outside of something?
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Old Dec 6, 2006, 12:27 PM   #6
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quite a lengthy read, but i think i got the gist of what you are wanting to do and im affraid it cannot be done, the only way a panorama works is if u keep stationary and turn, you cannot do it by moving, so inside looking out is fine but not outside looking in

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Old Dec 6, 2006, 9:25 PM   #7
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Of course I'll take "impossible" as a challenge.

I did the outside of a 2-liter bottle of Coke. And of course I could have just peeled off the label. I could do the same thing walking around a house.

To avoid background images I filmed this outdoors at night. The flash makes a blown-out line on each frame, and the narrow neck didn't get aligned. I cheated: instead of moving around the bottle, I set up the camera on a table-top tripod on one corner of a small table and put the bottle on the opposite corner, and rotated the bottle. I shot in landscape and cropped the images to a narrow aspect ratio portrait.

Autostitch couldn't finish this, and Canon EasyStitch couldn't either. ULead (PhotoImpact)'s Cool360 handled it. The viewer applet (not uploaded here) exaggerates the perspective, so while it is possible to go around and around the bottle, it's distorted from what would be seen normally. I suppose it's what you would see if you peeled the label, pasted it to the inside of a bucket, and put your head in the bucket.

I think this would work for the Common, outside looking in, if I did it at night with a flash to avoid seeing things on the other side.


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Old Dec 9, 2006, 10:16 AM   #8
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a couple of points to note, the camera never moved position and u turned the bottle,that will work as u have shown, as its only 2 dimensional,but get outside and try moving around an object 3 dimensions come into play, ie position of other things between you and what your taking a shot of.

i tried this a few years ago taking a panorama of a stretched hummer limo, took one shot, steeped a bit to the side......took anohter etc, background was impossible to join up but hummer was ok........i took one where i stood still and turned my body and that was perfect

ill try dig em out as i still have the snaps i think, but am in middle of a night shift at moment but it wont be for a couple of days
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Old Dec 9, 2006, 1:19 PM   #9
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Once you've got background or foreground, yes it's going to be impossible.
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