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While traveling to Europe, I come across many huge cathedrals and churches.

I normally take multiple zoomed photos of the building and then stitch them in photoshop. However the final result is not always desirable. Mostly they are distorted from the top and inflated overall.

For example:

Desired photo: enter image description here

Source: http://www.marburg-net.de/elisabethkirche.htm

Photo taken and stitched by me: enter image description here

Another example of photo taken and stitched by me: enter image description here

In the end I just want to know what I might be doing wrong and any help to take better photos or any post processing technique would be helpful.

Thanks in advance.

7

What you are seeing is a high amount of distortion, specifically barrel distortion.

One method to correct for this is to use a tilt-shift lens. You can use the lens manipulations to correct a great deal of what you are experiencing.

You can also account for distortion using post processing software. Modern panoramic software has the ability to account for multiple distortion types and barrel distortion is one of them. PTLens for example can account for multiple types of distortion(including barrel) all at once.

To achieve the "flat" look that you desire, you will want to use a rectilinear projection in the software you are using.

See this for more information: What are Barrel and Pincushion distortion and how are they corrected?

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    Perspective is a factor, too. To get the same shot as the "desired" image, you would need to be further away. – junkyardsparkle Jan 2 '16 at 6:13
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    Also, with stitching, the final projection is more important than correcting barrel distortion of the original shot. If you want straight lines, you need to choose a rectilinear projection for the final stitched output. – junkyardsparkle Jan 2 '16 at 6:25
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    Also, it helps to use the same exposure for all shots in a stitched image. Either use manual exposure settings, or use the AE-lock feature to lock exposure for the shots. The stitching software won't have to work as hard to match edges and stitch the image, and you will have more choices where to place the stitching region (for software that allows the choice). – scottbb Jan 2 '16 at 18:04
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    @scottbb Yes that is true. That is a whole other topic I chose not to cover in my answer. The question is extremely broad in scope! Could easily fill a book. – dpollitt Jan 2 '16 at 18:05
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    @junkyardsparkle Thank you for your suggestions ... I will keep these in mind and try to follow all your instructions. – Gaurav Jain Jan 2 '16 at 18:11
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Don't use Photoshop's Photomerge to stitch; use a more sophisticated panorama stitching package that allows for perspective correction and a variety of mappings. You also need to work on your shooting technique.

The main issue here is the perspective, and the panorama's mapping. Some of the recommendations here, though, don't make a lot of sense. A tilt-shift lens might help with the extreme sort of keystoning you have here, but TS lenses are typically limited to only about 8° of tilt and 10mm of shift, and being designed mostly for full frame, they won't go ultrawide on a crop body, and shifting only gives you so much coverage. You really need a view camera where you can manipulate both the lens and image plane to correct for keystoning that extreme. Unless you have the correct working distance and focal length, a $2000+ 17mm TS lens isn't a practical solution for a lot of shooters.

However. You can correct for it in post with software, such as Hugin or PTGui. You can do this while you're stitching using vertical and horizontal control points. And you may be able to correct most of it on a stitched pano with simple dragging in the preview window (dragging horizontally corrects yaw, dragging vertically corrects pitch). But you also made some shooting errors.

Your camera is shifting position between shots, as well as varying in pitch and that makes for some weird distortions when you get around to stitching. My recommendation is to stop handholding and use a tripod, preferably with a head where you can rotate around the no-parallax point--although that's probably overkill unless you're within 10' of the building, or at least consider using a plumbline. If you must go completely freehand, in a pinch, consider balancing the camera's tripod hole on your thumb, to try and hold the camera in place, as you rotate it, to minimize movement.

In addition, you need to consider using projections other than equirectangular or cylindrical (the only two Photomerge can handle), and think possibly about spreading out to projections like architectural, Panini, or stereographic. Again, stitching applications like Hugin and PTGui allow you to select from a number of different projections.

You also need to consider shooting coverage in time as well as space, so that you'll have enough "clean plate" background so you can mask out ghosts and clones when subjects move through your member shots.

3

Let me start by saying that the first photo, the "desired" one, it's really terrible: look at the sky and look at the guy on the left's ghost.

For the best results in panoramas photo, maybe in order from easier to hardest

1 - Don't stitch thing by yourself in Photoshop. You have many option, and altough I can't tell you which is the best of the best, I can offer you a couple of advices:

  • Hugin is very good and gives you an amazing level of control over things.
  • Microsoft ICE gives amazing results but not much control over things.

I usually use both; Hugin to have a lot of control and more options, and ICE for those situations where the starting shoots are so good (from a panorama point of view) that they really don't need more than a 30 seconds click-click-click process. Sometimes I even use both, then decide. And Hugin has the amazing and unnerving capability to go in the totally wrong direction, sometimes. ICE is noticeable for other two things, too:

  • it has the capability to fill in voids (not that it can do that much, but when it works...it's a joy)
  • it can publish your panorama on some kind of viewer or such. But I've never used this feature, so I can't tell much more.

2 - Shoot in raw, if you can. You should try to keep your exposure constant during shooting, but using RAW allows you to correct a lot after. And both Hugin and ICE can load RAW, so they even can do all work for you (but I prefer to do that myself)

3 - When possibile to do it, moving around with the camera (but parallel to your subject, i.e.: keep the same distance from it) gives better results, reasons for this in point 4

4 - Don't rotate around yourself. Don't rotate around the camera body. You need to rotate around the Panoramic Pivot Point

5 - End of the previous page: if you fall in love with panorama photos, buy a really good tripod and panorama staff/stuff/thingie.

6 - Tilt'n'shift lenses can help, but not that much. Nearly nothing, honestly, unless you are trying to shoot a very vertical building. Because if you use a tilt'n'shift, shoot in jpeg, stitch in Photoshop, don't take care about exposure, and don't rotate camera properly, you just wasted a huge amount of money to have a terrible shot with a slightly better vertical perspective :-D

  • To everybody: "the guy on the left's ghost" it's blatantly wrong, but I can't came up with the right phrase, as English is not my first language. Can someone please give it a proper form? Thx :-) – motoDrizzt Jan 2 '16 at 19:36
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    I think the way you stated the ghost issue is just fine as is. I wouldn't change it. – dpollitt Jan 3 '16 at 4:34
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I have taken many successful panoramas of buildings around Europe and I can offer the following advice that might help here:

Software: Dont use poor stitching utilities like the one bundled with Canon cameras. I use Photoshop CS6's photo merge stitching feature and find it excellent in 9 out of 10 cases. There are probably better apps out there for this, but I've never needed them. It works fine if you use the right camera techniques.

Technique: - use a lens/focal length that has as little distortion as possible. A 50mm is usually a safe bet. - set your exposure to manual and carefully choose a single exposure setting suitable for the entire picture (be aware of areas of extreme contrast, such as the sun). - set your ISO manually as appropriate to the scene. - ditto for white balance; manual. - ditto for focus; manual.

All of the above points are to remove shot-to-shot variability, and avoid problems of lens distortion.

Orient the camera for portait composition and see if you can fit the height of the building (and a little extra buffer zone top and bottom) in the frame. Move back if necessary and try to avoid weird perspective by photographing from too close. In some cases you will need to take two or more rows of horizontal images (a matrix) in order to accommodate the required height. Again, be aware of your subject's perspective; some of the things you aren't happy with are simply perspective issues, so you need to change your position to fix them. Also consider the aspect ratio of the finished panorama. For example, a 10:1 image is very difficult to print well and doesn't fit well on most monitors, whereas a 5:1 image does. You can often simply add a bit of sky/foreground to make the image taller (or wider) to fix this.

  • Apologies for the poor formatting above - Android phone seems to suck at SE posting. – HamishKL Jan 2 '16 at 22:18
  • lens distortion is mostly irrelevant - all photos must be reprojected by the stitching software anyway. as a side effect, this also corrects distortions. – szulat Jan 2 '16 at 23:05
  • @szulat - depends on software, lens profiles. Easier to just avoid distortion in the first place. For comparison try taking a panorama with a 50mm lens, then make the same pano with a 20mm. Sure the 20mm requires fewer frames, but which one was easier to stich and looks better? – HamishKL Jan 3 '16 at 0:36
  • @HamishKL OP says the images were stitched in Photoshop, so not sure your software recommendation makes much sense. – inkista Jan 5 '16 at 2:59
  • @inkista Fair point, but I've seen people manually stitch panos in PS, and the stitching routines in CS4+ seem far better than earlier versions, for what that's worth. – HamishKL Jan 5 '16 at 18:16

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