Spherical Camera Stereo Render

[ronjart]

I was curios if anyone knew how to render a side by side stereo image with a spherical panorama camera. It seems like you can't just duplicate your camera and shift it a little (ipd) like you would with a regular camera since the 3d effect would only work in one direction.

Any pointers?

[maxuser2]

It's impossible to do physically correct, only fakes and tricks.

[ronjart]

But there is still the potential for the octane team to build in some kind of helper to make it possible to output side by side stereo panoramas right? Or are you saying that is just impossible to do (which I don't think it should)?

This would be a real great feature because it would allow for photo real VR panoramas - which would be really great for Arch-viz.

[kurtjn]

But there is still the potential for the octane team to build in some kind of helper to make it possible to output side by side stereo panoramas right? Or are you saying that is just impossible to do (which I don't think it should)?

This would be a real great feature because it would allow for photo real VR panoramas - which would be really great for Arch-viz.

I think it would be possible but rendering would probably be twice as long since and entirely new angle would have to be rendered. I am pretty sure I heard/read them talk about bringing it into version 1.5 (stereoscopic side by side) but they may of scrapped it for now because apparently they had to rewrite the code. I am looking for this feature too. Maybe they can write a rendering preset at least so that you can set the rendering from the right camera, then after it's all rendered , render the left camera... I know you are probably looking for something real time as I am just so we can set the stage properly and get the right effect.

[ivankio]

Real stereo panorama is impractical (to do not say impossible) at the moment and it has nothing to do with Octane.

What some are currently calling "stereo panorama" (like krpano.com), is actually a displacement off center of the re-projection camera (not the one in the scene that rendered the panorama). It's a space bending illusion mainly to increase your field of view without the non-uniform loss of detail natural to the traditional 3-point-perspective increase of FOV. But this so called "stereo panorama" is not able to produce a real stereo effect - where objects in the observed scene are seen with parallax.

panorama_01.jpg

Let me illustrate with this: http://www.animaokio.com/in/poeme/
The parallax option in the link above is what krpano calls stereo panorama. If you zoom out (actually a mix of zoom and dollying on camera parallax mode), you'll notice your position will be very near the sphere. Note also that when looking down, you are obviously not rotating immediatelly above the center of the floor. This is also used to create what's being called "little planets". But a parallax of the re-projection camera does not give any depth perception of the actual scene (and depth is what stereo vision is all about).

It's true that for a stereo image you do need only 2 side-by-side views because you have stationary eyes. But 2 panoramas taken side by side wouldn't produce the desired effect. It would be like looking back without moving your head and body, just the eyes loose in their sockets (crazy like that). I mean, "side-by-side" is relative - relative to your head, not to the observed place.

panorama_03.jpg

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I said impractical because you could in theory be able to produce a stereo panorama if you were to either:
1. Do the rendering in real time, but then it would be silly to constrain yourself to a single position and you would lose the advantage of low processing demand.
2. Render 1 movie with full vertical FOV per eye. Then instead of re-projecting the render into a cube/sphere and control the view, you actually use the horizontal input to play forward or back the movies of both eyes and you would have as many steps as you render frames. In web development terms: more like an object viewer than a panorama per se. A smooth panorama would demand a lot of megabytes on demand (scrolling video is not common). In such case, a stereo movie would probably be a best use of that data bandwidth.
3. Create a partial panorama (less than 180º), similar to keeping the head stationary and looking around. This can be achieved with regular cameras. You would still need to develop an application to view these and it's appeal is dubious.

panorama_02.jpg

Be careful with buzz words combos - or I maybe I'm outdated. Where was it seen?

[prehabitat]

if we ignore the 'Stereo' Part - as I'm not sure its relevant unless you're viewing it in flat 3D from a modern screen - I believe there is alot of demand for this panoramic VR in Arch-Viz at the moment. The firm I subcontract for was recently put under a great deal of pressure on a 80mill Aud project because of a few interactive panoramas of their building/project during construction.

Pano2vr was the product used in this case, but it did indeed require the panoramic image (spherical mirrorball image? I may be mixing my terms here). I believe 3DS can make these OOTB, then you just need a program to interpret them. (I think from memory pano-to-vr can stitch the images too, although I don't know how seamless it is?)

fwiw I believe it is possible to stitch these together again manually too; so perhaps rendering each 'tile' (for lack of a better term), the stitch the pieces together in photoshop later.

here is a list of links I found which seemed relevant at the time:
http://www.youtube.com/watch?v=lkEEfAOBAkw (3DS tutorial)
http://www.youtube.com/watch?v=Y3rol5UOSWw (3DS tutorial)
http://www.youtube.com/watch?v=jgAAyxqR ... D&index=93 (non-English 3DS totorial)
http://docs.autodesk.com/3DSMAX/15/ENU/ ... d30e443031
http://teocomi.com/360-vr-panorama-workflow/
http://ggnome.com/wiki/Pano2VR_Tutorials

[ivankio]

Prehabitat, Octane does already render panoramic images OOTB. The panorama I used to illustrate (http://www.animaokio.com/in/poeme) I rendered with Octane, no stitching required.

In your camera settings, look for "Octane camera type" and, instead of thin lens, set it to... panoramic.

About image output, cube maps (rendered 90º in every direction of the 3 axis) would be the optimal pixel/area often used for final display either in krpano, games and probably many others.
But latitude-longitude (provided by spherical cameras) is the easiest to work with, understand, store (single file) and is considered the standard to create and edit panoramas, also often used for HDR images used to light the scene.
Mirrored ball (fish eye) texels are troublesome to say the least and probably not the one they used.

For further reference: http://help.chaosgroup.com/vray/help/ma ... camera.htm

[ronjart]

Thanks for the detailed illustration.

I've done some "traditional" panoramas for a client as well a little while ago: http://www.pixeet.com/pano/DZNYNZRF

[ivankio]

Beautiful overall, but I'm particularly impressed by your fabric materials!
Did you render them in 4096x2048? The detail is just right even on a 1080p monitor.

[ronjart]

Thanks Ivankio, I've rendered it @ 6000px x 3000px