Rendering to flash inside Adobe After Effects

Hello I have been using After Effect off and on for a little while now. I get better and better each day. I am just wondering why flash renders are so big inside of after effects. I made a 30 second little banner add. It was 8 to 10 megs big. If I lower the quality all the way down it is like 2 or 3 megs with horrible quality. What is going on with this? I appreciate any help, thanks. :slight_smile: