It's interesting that the clouds overhead (in the Chinatown before and after pictures) are averaged out, but the clouds on the horizon are reasonably fixed. I'

It's interesting that the clouds overhead (in the Chinatown before and after pictures) are averaged out, but the clouds on the horizon are reasonably fixed. I'm guessing this has to do with the apparent rate of movement since the clouds directly over your head always seem much faster than those elsewhere.