Interesting to know. I had seen the same thing a couple times when panning large stills, but it was usually negligable so I ignored it.

I love learning.

However, I have seen this effect with only two pan points, diaginal from each other. The pan will make somewhat of an 'S' motion. Perhaps 'S' isn't a good description because it doesn't move back and forth, instead it will change direction as it moves. It will move to the side and down and then curve to make a more downward approach to the final point. I suppose a '~' would be a better description. How can you interpolate between two spacial points and get a curve? I understand how it works for three or more points. I wonder if this might only be apparent in the preview window, and once the pan is rendered a more accurate striaght line is created.