I have captured about 200 hours in H.264 320 X 240 form in CatDV, a tape logging program. I then export the preview movie clips into FCP 5. The files work fine when brought into the timeline, no rendering needed, but as soon as I adjust the opacity the red bar comes on and it says not rendered. This is all normal but whats wierd is it wont render anything. It just flashes the rendering box on screen and then does nothing.

I have checked capslock, checked my checkmarks, and changed the rendering scratch disk. It renders everything fine EXCEPT the h.264 files. What is even stranger, at least to me, is that the video says unrendered unless I adjust the size of the viewing area. If I get it just so, the video plays but slightly choppy.

I have a quad G5 with FCP 5. Thanks for any help.

H.264 is about the worst possible codec you could have chosen. That said, what's the codec you're editing in, your sequences codec?

Use QT to export the h.264 files to the format in which you will be editing, then import those files into FCP. h.264 is no good for editing.