Motion blur acts as distortion?

[Patrick Casey]

Hey there,

 

I've been doing quite a bit of roto work lately and I've noticed a strange optical artefact that I was hoping someone could explain the nature of. Now this material originated on film so I don't think that it has anything to do with video compression or the suchlike.

 

Sometimes when an actor quickly moves over an object that has well-defined lines (a window in this case) it seems that in the trail of the motion blur from the actor the lines _bend_ in the direction that the motion is going towards. I can't post any stills since the movie isn't released yet but if someone's seen this sort of thing before and know what it is then I'd be happy. It's not important for my work right now, but it'd be fun to know.

 

Cheers,