Friday, June 3, 2005

How to Make 3-D Movies With Poser

I'm really getting derelict in my duties of updating this webspace. The job situation mentioned in my last post has been rectified (I survived the cuts, and am keeping my employment), but my hours have changed. This has cut down on the amount of time a day I can spend working on the movie. My new strategy is to animate as much stuff as I can on weekends when I have free time, and then let the computer do the work during the week. I am one shot away from having the first complete sequence finished for the movie.

Now, the question has become - how do you make a 3-D movie using Poser? The whole concept here is to photograph your subject from two perspectives, separated by the distance between your eyes (approx 2 1/2 inches). To do this, I put a reference object in the scene (namely a simple ball) and tell the camera to always Point At it. Where the ball is positioned will be the screen plane of the shot - anything coming between the ball and the camera will appear to come out of the screen, anything that falls behind it will appear to receed into the screen. The ball is hidden in the final render by simply turning it off. The final render of this shot becomes the Left Eye view. Then, I rotate the camera on the Y axis 2 degrees to the right, and re-render the scene. This is the Right Eye view.

This technique works best when the camera is facing the object straight ahead. When the camera is tilted to look up or down at an object, the Y axis becomes useless, and I have to manually track the camera to approximate the perspective shift. This has resulted in a couple of errors so far, which has resulted in too much parallax (the seperation between the final images when put together in 3-D). Too much parallax, or worse, a misregistered image (when the Right Eye image is slightly higher or lower than the Left Eye) can cause some serious eyestrain in the viewer. So, some of these shots had to be fixed by adjusting the Right Eye image later in post processing. There are two shots so far in this first sequence that will have slight black bars on the side of the frame, because I had to slide the images together to correct a problem with depth (objects that were supposed to be at the screen plane were too far in front of it).

The two final images, if they were rendered without problems, are combined in a program called
Stereo Movie Maker to make both an anaglyph and field sequential version of the shot.