I have just discovered the editing my green screen footage in AE... I've never used it before but the results are a million times better than in Premiere.
However, when I come to export my footage, retaining the transparent background so I can take it into Premiere I'm getting huge file sizes and I don't know what I need to tweak / change... render time is over 2 hours for a 50 second clip....
I'm sure there is something I am not doing correctly.. any help would be amazing!
The time it takes After Effects to perform a Render will depend on several factors, in order to tell you if something is weird or not, you must first give us details about your hardware and software as well as the exact details of your clip, such as resolution, framerate, color depth, etc. Whether the final Render is more or less fast will depend on all this.