Stereoscopic setup.

Hey everyone, yesterday i was toying around to achieve stereoscopic rendering inside Blender (why i posted in “animation” in just a sec). I’ll briefly explain what i did to illustrate the problem i have (pls read carefully its quite hard to explain for me).

  • Duplicated camera, moved it a little bit on the side, so to have a left eye camera and a right eye camera.
  • Made a second scene inside my Blend file, to wich i linked all objects.
  • Assigned the left camera to one scene and the right camera to the identicall second scene.
  • Made a simple node setup to make both scene render one on the other, but one only with red channel and the other with both blue and green, this way obtaining the usual red/greenish anaglyph combination.

Now, all of this is nice and works fine, but here comes my problem. Camera’s need to always be one side the other and also point at the same point.
So:

  • I made two empties, one to control the movement of both cameras and the other controlling the point to wich the cameras look.
  • I made the control empty as a parent, then the 2 cameras as sons, and also the “point to” empty as another son of the first empty. I assigned both cameras to llok at the “point to” emtpy.

Now i could move everything by moving the first empty, and point both “eyes” by moving the second empty. It works fine if you point this litle sistem just ahead of itself, but when you want o point up vertically or rotate the control emtpy, the cameras will stop being alligned horizontally and twist themselves.They still are dependant from the control empty and still look at the “look to” empty, but they cease being one at the exact side of the other (figure a binocular, both lenses are pone side the other at all times, but you twist their relative positions…here the same happens but what is needed is quite the opposite.

Does anyone have a nice tip to solve this issue? I will try to explain better if the way i explained was to complicated. :spin:

I have been able to do this successfully in the past. I’m not sure I fully understand your setup, but I think I can explain what I did differently. I started with a central camera and did all of my camerawork and animation there, with any constraints that you need to make it work. Then I made two identical cameras parented to the central camera on either side for left and right, and did the same Scene linking thing that you did. Make sure the new cameras do not have any constraints or animation data. With your central camera, make an empty that rests directly on its line of sight. That will be your convergence point. Parent that to the central camera. Now add the “point to” constraints to the side cameras targeting the convergence empty. Checking Target Z keeps the side cameras from tilting when you rotate your central camera. That should have you all set up. Animate the central camera however you want, and the side cameras should follow correctly. You can move the convergence empty along the line of sight to change convergence, or increase the distance between the side cameras to increase depth.

I made these pretty quickly, stereoscopic still technically (go crosseyed, or in my case which not many people can do, lengthen my visual focus. It can hurt a little bit sometimes I warn though…)

And this was done with a setup similar to yours, just with some other little compos setups. To get them side by side like that. I would render an animation but it is a bit slow on my computer :stuck_out_tongue:

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Mike, my setup is like yours, except that instead of a central camera i have an Empty. The two side cameras are parented to the empty (lets call it he “Driving” empty).
Then there is a second empty that acts as convergence, just like you did.
But if i point the “driving” empty in vertical and then play with the “convergence” empty, the 2 cameras sometimes rotate in opposite directions…a bit like binoculars would do.

Did you try pointing your setup vertically? Its also fine for me if i dont point the “driving” empty vertically and rotate.

I did try that, and didn’t have any problems. And you are sure that the convergence empty is parented to the driving empty? Also making sure that you only move the convergence along the line of sight of the driving empty? You might try adding a copy rotation constraint to the side cameras targeted to the driving empty and move it above the track to constraints.