Thanks to Andy Peterson for providing guidance on how to do this.

• execute the following command to set up povray environment (you only need to do this once):

  cp -r ~cpo/.povray ~

• Run ag on suncatls{}[1:3]. NOTE: you must use the ag in /afs/slac/g/suncat/bin since that is a script which adds povray to your PATH.
• Select Tools->RenderScene*. For the "quick and dirty" approach, you can select "Render all frames". I believe you can also render the frames one at a time if you want to change viewing angles, for example. Povray, which does the actual fancy shading, etc., should run automatically, creating many .png files.
• use a command similar to the following to create the movie. You will have to modify it to reflect the names of your .png files. Also, the "%02d" field is appropriate if you have between 10,100 frames. You would have to change it to "%03d" if you had between 100 and 1000 frames. The "-qscale" flag controls the movie quality (1 is the best, but takes up the most space). "-r" controls the frame rate. NOTE: quicktime doesn't support all frame rates (the symptom of choosing a bad frame rate on my mac is the images look messed up). Empirically, 1 and 3 Hz works for quicktime.

  /nfs/slac/g/suncatfs/sw/external/ffmpeg/bin/ffmpeg -qscale 1 -r 3 -i qn.%02d.png movie.mp4

• if you want to render every nth frame, you can use ag to select the pattern you want.  For example, for every second frame:

  ag x.traj@::2