No Video (Black Picture) After Effects Export

[Redsack]

I have a AE project that is about an hour long and when I export it, there is sound but no video. Any ideas? I am using seven different Final Cut Movie files in a composition (all Apple Pro Res 422) to be graded, etc. I've noticed that when I stopped the render about a quarter of the way through, the file was viewable. I have a deadline this week and I'm at a loss. Please advise.

Thanks.

 

[xenogears]

That´s weird!, try this at home... Make shorter renders, of 10 mins each and then put then on together in FCP too see this helps.

 

[Redsack]

It was the length. I trimmed the comp to shorter sections and exported each and it worked.