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I just got some vr cups and tried out the Cardboard Camera app, but the quality is pretty poor, and it's really intended for panoramas. If you have created stereoscopic (NOT panoramic) images for Google Cardboard that you're proud of, please outline your process.

This question is mostly how to edit two images into one that can be viewed with Cardboard, but if you have tips on equipment to use to take the stereoscopic images in the first place, those are very welcome as well.

I realize there are a lot of options. I welcome them all, and I'll upvote every answer I learn something from, but I personally need a solution that is fairly accessible. I need to be able to do it with one camera, and without having to spend more than a few minutes editing an image (not counting the learning curve). I use Gimp, and have a reasonably good 13MP camera on my phone.

2016 May 5 edit:
Note that this question is specific to Google Cardboard. I should be able to open a viewer app and switch to Cardboard view, including scanning the QR code for the specific Cardboard viewer, and have the stereoscopic image render correctly for that viewer. So probably, just creating a regular JPEG consisting of two images side-by-side isn't enough. What format is right for a stereoscopic image to be compatible? What metadata needs to be on an image for a viewer to recognize it as stereoscopic? What viewer app do you use?

Google's docs mention the "equirect-pano" format, but I don't see any documentation on that at this time. Also, this question is not about 360 panoramas, so if the equirect-pano format is the way to go, how would you represent an image with a 60° span without just leaving most of it black? (FYI, even if compression culls out all those black pixels on disk, the same is not true when the app loads it into RAM, which could cause apps to crash attempting to load high resolution images.)

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  • \$\begingroup\$ Since this question is less about how to take a photo than it is about how to edit and publish the photo, maybe it should be migrated to StackOverflow? I'm not sure how to do that. \$\endgroup\$ May 5, 2016 at 22:30
  • \$\begingroup\$ You can always migrate a question by simply creating a duplicate on the other site. You should include a clarification about your reason to do so and possibly link to this question here (if you don't delete it) as I have seen it many times that cross posting a question on many sites without clarification is not well received. Good luck. \$\endgroup\$
    – null
    May 9, 2016 at 22:28
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    \$\begingroup\$ You might ask, rather than this exact question a different one instead: Is there a mode or format for google cardboard designed for 3D images that are not panoramas or 360s. \$\endgroup\$
    – wedstrom
    May 10, 2016 at 16:02
  • \$\begingroup\$ @wedstrom yes, if someone answers that question, I could accept that answer, but really it's not quite the same question. If I don't get an answer I could award this bounty to, I'll ask that. \$\endgroup\$ May 10, 2016 at 16:57
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    \$\begingroup\$ Your edit has broadened this request to basically asking someone to write you an entire user manual on how to create a Cardboard VR stereo photograph. One question per question, please. \$\endgroup\$
    – inkista
    May 10, 2016 at 18:04

3 Answers 3

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how would you represent an image with a 60° span without just leaving most of it black?

You can't do it without leaving most of it black. With a 60ºx60º image, you've only covered 1/18th of the 360ºx180º view, after all.

Cardboard, being first and foremost a VR viewer, requires equirectangular input to represent the entire VR environment, so whether or not you are interested in creating 360ºx180º panoramas, that's what it's expecting: either a single equirectangular for mono view, or two stacked equirectangulars (left on top of right) for stereo view. But you have to have equirectangulars because most users of Cardboard are gonna want to turn their head to see what's to the sides and behind them.

If you want to use only a single 60º-coverage image, you're going to have to fill out the rest of the "space", somehow. The simplest way would probably be to just load your image into Hugin, set your projection to be Equirectangular, and stitch/output the panorama. The steps in my 2014 OSX version of Hugin are:

  1. Open Hugin.

  2. Select Interface → Advanced, because the default Simple interface won't let you stitch a single image.

  3. Click the Add Images... button, and load the left view.

  4. Make sure the Lens Type is Rectilinear, and if the EXIF didn't pull in focal length and crop factor, guesstimate your field of view.

  5. Click OK.

  6. Click on the GL preview button it the toolbar.

  7. Select the Projection tab.

  8. Make sure the Field of View is set to 360 x 180, and that the Equirectangular projection is selected.

  9. Close the GL preview window.

  10. Click the Stitcher tab.

  11. Set your output format and size, and click the Stitch! button to make your equirectangular.

  12. Repeat all this for the right eye image.

  13. Open both equirectangulars in the Gimp, and make a square image with the left-eye equirectangular above the right-eye equirectangular (equirectangulars are always 2x1 aspect ratio).

But you're basically going to turn this:

enter image description here

into this:

enter image description here

If you're not starting with equirectangulars.

Shooting and stitching a high-quality 360ºx180º is both equipment and labor intensive, so within your limitations of a) only using an Android phone camera and b) not wanting to spend a large amount of time post-processing, the Google apps (Cardboard Camera, Street View) that do Photospheres are probably your only way to do this, and you won't be able to achieve high resolution/quality, because you can't control the stitch, and you won't have the best optics or control for the job, not to mention a way to control rotating around the camera's no-parallax point, if you're shooting in a smaller space.

Typically, people who shoot these kinds of images do so with a fisheye lens on a dSLR, with a panorama head, and stitch with packages like PTGui or Hugin. The Gimp or Photoshop alone can't do this particular job. And this type of shooting/stitching isn't particularly easy to master. (See How are virtual tour photos taken?). And then you'd have to find some way to duplicate Cardboard Camera's computational ability to create stereo images from a single image, much as 2D-shot movies get 3D-ized.

Everybody wants high quality for free and little-to-zero effort, but it's rarely a possibility.

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  • \$\begingroup\$ Thanks inkista, and maybe you're right that "you can't", but you're really focusing on the topic of panoramic photography, not stereoscopy. I've used Hugin, but I didn't think it addressed stereoscopy at all, and a quick web search seems to confirm it still doesn't. An equirectangular projection alone can't support stereo because the position of the two perspectives actually changes continuously. Maybe you know all that. Regarding quality, I'm satisfied with what my Android phone produces, I just don't know how to make an image to view through cardboard. \$\endgroup\$ May 10, 2016 at 16:52
  • \$\begingroup\$ @TravisWellman In addition, I'm ignoring your edit, because at that point, the question's expanded well beyond what an SE question should hold. One question per question. Nobody's going to write an entire user manual as an SE reply. \$\endgroup\$
    – inkista
    May 10, 2016 at 18:13
  • \$\begingroup\$ Also, I think you've figured out why the majority of stereo Cardboards are CGI, and the majority of photographic/video ones are mono. \$\endgroup\$
    – inkista
    May 10, 2016 at 18:14
  • \$\begingroup\$ @instika If you delete the last three paragraphs of your answer, and more directly address the first paragraph of my question, this could be the best answer I'll get. It may just be that Cardboard is designed for panoramas, not stereoscopic photos. I really appreciate the illustrations. \$\endgroup\$ May 11, 2016 at 19:15
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There are a few companies that sell stereographic lenses for SLRs. Limited set of focal lenths but it should do what you want.

One example is the Loreo 3D

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  • \$\begingroup\$ Yes, I had found this answer that lists Loreo as well as Kula and the Samsung NX300: photo.stackexchange.com/a/72999/47945, but this question is more about what to do with those images to make them viewable in Cardboard, including whether the photograph needs to be taken a certain way. \$\endgroup\$ May 10, 2016 at 16:35
  • \$\begingroup\$ It should work with any stereographic viewer. If you open the picture on your device you will see two images side by side. The "cardboard" viewer will just block your vision so you can only see one of the images with each eye. The difference in the images will make the image appear 3d. \$\endgroup\$ May 10, 2016 at 16:43
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    \$\begingroup\$ If you look at the way the phone renders before you put it in Cardboard, it distorts the image significantly to match the viewer you scan with the QR code. It's not just a "flat" image, and it's not the same distortion between different viewers. How do I achieve that? \$\endgroup\$ May 10, 2016 at 17:03
  • \$\begingroup\$ That I have no idea. Have you tried just looking at the image normally and not with a special app. \$\endgroup\$ May 10, 2016 at 17:16
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Take photos with a camera that can produce .mpo files and use the Cardboard MPO Viewer.

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