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How can I capture a photo similar to the example in a tight space?

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I've research lightly for a solution to make a picture/scan of an entire wall of a room in a semi- orthographic fashion. I imagine it would work similar to the scanning wand in a copier.

Things I've tried:

  • Currently I am taking multiple photos, correcting their perspective, and stitching them together in a very crude way.

  • I've tried to use an iphone panorama, but that only works from one spot with rotation and not with lateral motion.

A similar question to this in a larger space required is here: How can I stitch a panorama correctly if I moved the camera along the horizontal axis?

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  • Question: I found that that recommended similar answer, photo.stackexchange.com/questions/14658/…, is helpful, but not identical due to the limitations of "scan" being excluded from the text. Can I link the parts that are helpful here such as: Itai, parallel motion panorama. Inkista, You can use mosaic mode in Hugin for these types of panos.? The solutions are the best for my problem here when forced to be in a confined environment with almost no room for anything more than ultra-wide focal length or scan. – cliffclof Nov 29 '16 at 6:12
  • Also, Check out these options: Microsoft "Image Composite Editor", and iphone ipad apps titled: Slit Scan, and ScanCamera. They are the best options but distort images so much because they use the camera's video mode to capture. Hugin is a great suggestion. The other suggestions such as Occipital's structure sensor, and Microsoft Photosynth were neat, but unrelated to my specific case. Thanks! – cliffclof Dec 20 '16 at 23:48
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Currently I am taking multiple photos, correcting their perspective, and stitching them together in a very crude way.

Yep, that's exactly the way to do it. Good, modern panoramic software should make this less crude. If you use a longer focal length and take many, many pictures, your result will be better — maybe somewhat painful, but you know what they say about free lunches.

If you do this a lot for some reason, you might consider creating a rig of some sort to make the repetition easier. For a one off, though, I'd use a tripod with a lot of variability in height — set it as low as possible, take a picture, move (possibly some gaffer tape on the floor to make it easy to know how much to move), click again, and repeat. Then, when you get to the end, raise the tripod, and go back the other way. (You become the "scanning wand", in effect.)

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A series of slit photographs taken along a path parallel to the wall and over the length of the wall could be stitched together to provide an orthographic image. Not quite strip photography at the pixel level but the same general principle.

Setting up a track along which to move the camera, measuring distances, and moving the camera with precision are more a less an engineering exercise in technical photography that has to balance effort and expense with the value of accuracy in the results.

Google experimented with [and rejected] a similar approach for Street View early on.

  • I like this link to strip photography and street view slides. That shows many examples useful in an inward and outward facing lens on a trajectory and fixed. Plus, Calvin and Hobbes. – cliffclof Nov 29 '16 at 6:27
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    @cliffclof The slides are from Mark Levoy's free online Digital Photography course. I thought it was awesome, but what do I know? sites.google.com/site/marclevoylectures/home – user50888 Nov 29 '16 at 13:56
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As this is a photography forum, I should mention a shift lens, which can correct some of the distortion in one axis.

But in a tight room you probably need to use a wide angle lens, which is more problemathic.

There are some programs that recognize the specific deformation of some specific lenses and help you to correct them pretty quick, for example DxO: http://www.dxo.com/us/photography/community/tutorials/getting-started-dxo-viewpoint-2

  • Do you mean shift lens? Tilt won't correct for distortion, it will just create a plane of focus that is not perpendicular to the lens axis — Scheimpflug. – scottbb Nov 29 '16 at 2:46
  • Oh, yes, I meant shift. – Rafael Nov 29 '16 at 3:05
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If I understand your problem correctly, I would suggest two methods:

  • move away as far from the wall as the room allows and from there take photos with the appropriate focal lenght or
  • take multiple images and stitch; for this task i would suggest Hugin. It takes a bit to get used to it, but is very good for perspective correction and stitching.

As for a single machine/camera, that is able to scan the wall and make a fully orthographic picture: I don't think this is available. The "scanner" would have to have the same size (at least sam heigth) as the wall. Talking many, many pictures and stitching them together could kind of simulate a scanning behaviour, but I doubt the results would be very good and worth the work.

  • Don't know whether it still exists, but Microsoft a few years ago had an experimental website where you could upload a lot of photos of an area. The server software would analyze it, detect common features, and stitch them all together so that you could navigate around, like in Google Street View only smoothly. – WGroleau Dec 9 '16 at 23:23
  • I checked that out back then, Microsoft Photosynth. Pretty cool, but more for single focal point focus when i tested it. Thank you! – cliffclof Dec 20 '16 at 23:46
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Not a perfect answer, but a way to reduce the problem: Put the camera in the middle of the wall, and put a big enough mirror on the opposite wall. Effectively doubles the distance, thus reducing the angles.

I don't know whether this exists, but I envision a camera that slides along a track parallel to the wall and has a cover over the film/sensing surface with very narrow slit that moves proportionally to the distance along the wall.

  • Nice thoughts, thank you. Both are very outside the box and helpful. The mirror would be tough to do and the slit version is interesting. Thanks – cliffclof Dec 9 '16 at 19:37
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Is Occipital's structure sensor close to what you envision? http://structure.io/

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