Re: resolution in AE

Thanks for your response, I understand now how a composition takes over the resolution of imported (nested)composition. This is good for rendering. But if you want a high res. still from this composition (for publicing) you got a problem because, in my case the composition is made in PAL.

You refer to help page collapse transformation. Where can I find these?

Here's where Collapse Transformations comes in. Read the help page to see what it does, and then try it out :) It will allow you to get the quality you want in the final render (but it does get tricky when you combine it with 3D stuff and effects, sometimes it takes some wrangling to get what you want without side-effects).