There are many Harry Potter "how it was done" blogs, you want to try searching those. Dozens of effects and compositing shops were used in each film.
After Effects probably showed up in every shop's preplanning and animatic stages, maybe even in rough assembly.
I think if After Effects was used extensively in the actual film, Adobe would be all over it and I have not seen such.
Thanks will look into that now !!
After Effects is used all the time for feature film and commercial work. Everything from pre-viz to compositing to title graphics. The Monsters Inc. titles were all After Effects.
There used to be a list somewhere and it was a long one. You might want to take a look at this article.
Great to know that , any other links as far if it was used in any HP ?
"I think if After Effects was used extensively in the actual film, Adobe would be all over it and I have not seen such. "
That depends. Many shops don't want to publicize that they use AE on final shots for feature films. This only tends to re-inforce the fact that other shops don't mention it either.
Unless a shop specifically tells Adobe we can talk about it publically, we keep our mouth shut.