Why does panning look "jittery" at Cinema?

[Bingo Bongo]

....but not on DVD?

Especially wide sweeping pans like in LOTR, they look blurry, yet similar shots on DVD look pin-sharp

[Squirtle]

NTSC cinema? :D

[utero]

the bigger the picture, you have a far greater area to focus your eys on in a cinema

[SithLordSi]

It's also because film runs at 24 frames per second, whereas PAL runs at 25 frames per second.

[Confucius]

Film can be quite unstable - strips of celluloid running at high speed round lots of pulleys with sometimes quite old equipment - which is why digital cinema, of lower resolution than film, can look much better.

C'est la vie.

(the 'size' factor is also significant)

[john316]

How many cinemas in the UK operate with Digital Projectors now?

[THX 1138]

Like it has already been said, it has to do with how many frames per second, and also remember that your TV and player also run at 50/60hz stopping the flicker of film which runs at 24 frames a sec. Using a pc can also up that to even more refresh rate.

There are also artifacts to take into consideration like 3:2 pulldown on ntsc signals.

size has very little to do with it, look carefully and you will see it even on a 32" tv.

It's just one of those things