You have an effect or setting that behaves differntly during life previews and rendering. Could be something with OpenGL, 3D rendering, layer styles and effects, could be an effect that is not safe to use with MP rendering and thus disables itself. Definitely not a general problem, but rather quite specificly tied to one of these things. If you can provide more details, we may be able to advise further.
What other details about the project/comp would you like to know? I did have Multiprocessing turned on, so since you mentioned that I tried rendering again without it on...no fix.
As far as effects I'm using: I have CC Sphere & Glow (for each of the planets); Shatter (for just one of the planets); Text with ramp, drop shadows, and bevel; there are two ".Mov"s in the comp (one of them with a color key effect). That's about it.
For further settings that I am using, see pictures:
Media/Disk Cache Settings:
Memory/Multiprocessing Settings (keep in mind I've changed this up different ways trying to make it work, this was what I used for the last attempt):
Also it might be important to note that I do have another composition that is exactly the same (which renders out perfectly), only difference is one of the planets doesn't explode. So maybe there is some setting with the effects on the comp with the exploding (using Shatter effect) planet. Thoughts?
OK! I figured out the fix...I just made all the layers not 3D and now it renders without scaling anything up. Interesting though...Still not sure why it renders differently than it looked in the Preview.
YOU SOLVED IT! I had "fixed" it by taking all the layers out of 3D. But really my issue was that I was viewing the "front" and not the active camera. I didn't realize it made a difference unless I actually had a camera in the comp. But I went back to the original comp that was scaling during the render and changed the camera view to active and sure enough it was all scaled up. Good to know now that the "active camera" is what will render out. Thank you, Todd!