DVD rip looks crappy when imported into After Effects

OK, here's the deal: I ripped Phantom Menace using DVD Decryptor, and then duplicated the VOB file and re-tagged it as an MPG. I also trimmed down just a little bit of the VOB using MPEG Streamclip and renamed it as an MPG and tested it in After Effects, and it worked fine. But then, when I imported the fill movie, it looks like crap. Compression artifacts, grain, every problem up the wazoo. I have no idea what the problem is, since theoretically the only difference between the big file and the small one is size.

Anyone know what could be the culprit here, and what I can do to fix it? Like I said, when I used just that small clip earlier it looked fine, but when I worked with the full movie it looks worse than Youtube quality.

VOB and MPG are actually the same thing, it's just that the name of the container file is different. Most programs don't read VOB, but if we rename it as an MPG then we can trick it into reading the contents. It's the same story with a demuxed M2V file, and unfortunately, that means that demuxing is not a way to escape After Effects' wrath. I'm gonna have to go over there to render the file anyway, since my laptop would fry trying to do it.

I really don't get this. If I make a small clip of the file, depending on what part of the film it's from, After Effects might except it. For other parts of the film though, I get the same problems, and if I try to import the whole film then the whole thing looks pukey. I can't figure out what variable is causing this to muck up, which is very frustrating. Maybe I should try doing this on one of the computers at school tomorrow.

Oh, and before someone jumps in and says "Convert it to DV!", I'll get it out of the way right now that I don't want to use DV because there's no way to export a DV file at 23.98 FPS using MPEG streamclip. My only option is 29.97 FPS, which would cause me all kinds of problems.

Also, after poking around a bit it sounds like this problem has been fixed in newer versions of AE. My school's copies are probably much more up-to-date than mine, so I'm hoping I can get the color correction all squared away at school since that means I won't have to add an extra round of compression to my edit (which is particularly important to me, since one of the goals of my edit is to improve the picture quality over the official release).

OK, I'm at school trying to import the .MPG file into after effects CS4 on one of the school PCs, but instead of the problem I had on my Macbook Pro where it would look crappy when imported, on the school PC it seems like After Effects just plain freezes up when I try to import it.

Am I going about this the wrong way? I was under the impression that color correction should be done to the footage before editing starts, but I heard that there are other people who will do the editing first and then take care of everything in After Effects afterwards. This would certainly solve some problems for me, since After Effects seemingly refuses to load the MPG files correctly, but they work fine in Premiere. If I did the editing first and then saved the color correction for later, that would save me a lot of trouble (although I am a bit worried about the footage being re-compressed too many times if I accidentally do this in the wrong order).

OK, from what I can tell after trying to get this to work on the school's computers, the problem is that the video file is so friggin' big that the Adobe programs are somehow getting overwhelmed. I think that the solution is going to be to break the video file up into several chunks and then reassemble them in Premiere, because it seems to accept shorter MPG and M2V files. The question is, how small do the files have to be? I've already tried cutting the film in half and that was still too big, so now I'm trying to see if a 30 minute chunk will do the trick.

OK, screw that, now I am converting the whole file into an MOV encoded with the Apple DV codec at 100% quality. I'm guessing that this file is going to be a beast in terms of HDD space (it's currently converting, slowly), but from what I understand that's the best option to go with. I'm still new to all this and understanding how to make an efficient work flow is something I'm still learning, but right now it's looking like DVD Decryptor > MPEG Streamclip > Premiere > After Effects > Premiere > DVD editor (not sure which one to use yet). I'm also going to have to "obtain" the Dolby plugin for Premiere at some point so that the 5.1 audio which I fought so hard to import will be in tact.