Just out of curiosity, what are you using AE for? Unless you’re doing some swooshy motion graphics or compositing, there’s really no need to step out of your editing program.
But, on to your issues.
For one thing, you don’t want to use the straight MPG files from your camera in After Effects. AE is not a video editing program. It handles video very differently from Premiere, Final Cut, Vegas, etc. and AE doesn’t play well with MPG video. Dave LaRonde explains why:
Dave’s Stock Answer #1:
If the footage you imported into AE is any kind of the following — footage in an HDV acquisition codec, MPEG1, MPEG2, mp4, m2t, H.261 or H.264 — you need to convert it to a different codec.
These kinds of footage use temporal, or interframe compression. They have keyframes at regular intervals, containing complete frame information. However, the frames in between do NOT have complete information. Interframe codecs toss out duplicated information.
In order to maintain peak rendering efficiency, AE needs complete information for each and every frame. But because these kinds of footage contain only partial information, AE freaks out, resulting in a wide variety of problems.
And Adobe agrees.
So Render out of Vegas something you want to work with in After Effects. I’m not sure what options Vegas has, I’ve never worked with it.
Now, as to your aspect ratio problem: After Effects is not “destroying” your video. You are. 🙂 It’s only doing what it’s told to do.
You need to tell After Effects how to interpret your footage. I would suggest you import your footage and then just drag it onto the new composition button. It will then create a composition to match the footage. There is an aspect ratio correction button at the bottom of your comp window. You may need to push this button to get it to display “correctly”. Then, when you output your video with the Render Queue, you will need to make sure the video you’re outputting is the correct aspect ratio as well.
You can read about interpreting footage here and you can read about rendering here.
Also, since you’re wanting to put out videos for your friends to see, I shall point your attention to another Dave LaRonde thing that will be useful for you:
Dave’s Stock Answer #3:
Don’t use AE to compress files for final delivery. The various compressors are there…etc. AE is incapable of doing multipass encoding, a crucial feature that greatly improves the image quality of H.264 and MPEG-type files in particular.
Render a high-quality file from AE, and use a different application to do the compression. Popular ones are Adobe Media Encoder, Sorenson Squeeze and Apple’s Compressor, which comes bundled with Final Cut Suite. Even compressing in Quicktime Pro is better than compressing in AE.
Making good-looking compressed files is almost as much an art as it is a science. It is NOT straightforward at all. I recommend asking a few questions at the COW’s Compression Techniques forum.
This is a professional program, intended to be used by people with exprience in the industry, so it can take a while to get used to all this stuff.
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