You must provide us with your project and render settings. One or both is or are obviously not correct. Have you ever successfully rendered out of AE before?
1. Why are you using a green background?
2. But try this: in the same project, create a new comp. Copy and paste your text layer into the new comp. Do not use a background plate of any kind. Turn off motion blur and anything else that might alter the image.
3. Save a frame, any frame. Open it in quick view or photoshop. Is it nice and clean?
4. If not, we have other issues and the more experienced wonks will need to help you.
5. If it is crisp and clean, try to render.
6. If that works, try rendering with motion blur active.
7. If that works, render using a codec that supports alpha.
8. Import the rendered movie and place it over your green background if you need the green.
The background is green because we key it out in another program that we edit our News material in.
I think i found the problem. When in the render settings, a "Settings Mismatch" error pops up on the bottom. It says that it will knock down the rez to 177 from 1080. This only occurs when saving to MPEG4, so I tried saving to Quicktime and everything was fine.
Groovy. And thanks for posting your solution, hardly anyone does that around here.
Back to the green thing. Can't your news editor process an alpha? Keying out the green, no matter how good your keyer is, adds an unnecessary step and introduces edge artifacts. The MPEG4 compressor also adds a significant amount of compression artifacts by its very nature. Suggest you use ProRes4444 with alpha active or ye olde Animation with millions of colors+.
The news program is for a high school. I am planning on teaching the alpha to my next group of students. But for now, since is it mid semester, I am keeping things the same.
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I've been teaching After Effects for 20 years and been in broadcast for more than 40. I've never seen anyone use chroma key for titles. Even. Don't mean to throw cold water on your lesson plans but you are teaching a useless skill. Keying should be used for an entirely different process.
That said, you'll never get a good MPEG compression with white pixels next to green because of color artifacts generated at the edges when the values are so extreme. Even JPEG compression would give you color artifacts that will make your cities look awful.
If you are using white titles and you don't want to teach alpha channels then render them against black and use either luma key (also a bad choice) or screen blend modes. Even if you are running your titles to tape and running the news show through a really cheap switcher this will work better.
Also, if you are teaching production, you should introduce your students IMMEDIATELY to the concept of Production Masters as uncompressed or lossless formats. If you have taught them to render mpeg files or h.264 or other formats as a DI (Digital Intermediate) or Production Master, then they are going to have to unlearn what they have learned to produce high quality work. The most asked question on this forum, or on the PPro forum, or on Final Cut, Avid, or any other forum I have ever seen about rendering and quality always have the same answer... "Render your production footage to a suitable production format that is lossless or Uncompressed (and if possible at least 10 bit)."
Almost every problem rendering text comes down to huge differences in the values of the background and foreground, as in your example, line width, and roll or crawl speed and these problems are always handled best by bringing the values of the text into a usable range and by rendering a DI with an alpha.
One more thing. The RGB values of your green background are 16, 234, 33 which leads me to believe that the original is probably pretty close to 0, 255, 0. When your green is so saturated and the values are so high, even if the original was 16, 234, 33, you have seriously limited the headroom in the green background that is required to pull a good key. If you had a person with light brown or blond hair against a green background that hot you would not be able to pull a decent key with any software I know of. Here's why.
Say your Project settings are 8 bit and your green value is 233. Now the edges of your subject, in this case your type, are not going to be perfectly lined up with the pixel grid so some interpretation of the pixel data is going to happen. Lets's say that the value of your type fill color is 255, 255, 255. When the type is slightly out of alignment with the pixel grid, as it must be in curved letters or with fonts that are not specifically designed to line up with the pixel grid, the edge pixels get assigned other values. The difference between 255 and your background of 233 leaves you with only 22 possible values to use to create a nice anti aliased edge that will look good. In practicality, because theres is no room in the text you really only have half that. This guarantees a less than optimum key quality and jaggy edges. You should never have the background of a keyed shot with a higher luminance value of the average caucasian face. 10 or 20 points lower would be better. This gives you the maximum ability to generate blended edges that look good.
Incidentally, the extremely narrow range of values between your green background and your white text is also the thing that causes image compression to generate ugly compression artifacts. There's just not enough difference between the two to do a good job estimating edges that don't line up with the pixel grid. The same thing goes when you have black and white (0,0,0 against 255, 255, 255) There's no place to go so the artifacts in the edges are horrible.
I hope this helps. If you want your students to get a good handle on production techniques think hard about modifying your lesson plans to teach them the right way to do things first.
As one who has gone round and round on this topic with a friend who's in charge of the daily school newscast and teaches a high school TV Production course, I agree with Rick.
After too many hours of frustration dealing with lousy-looking animated graphics, my friend eventually and unwittingly agreed with Rick, too.