Images: .png vs .gif

Hi.
I have been expiramenting with imported images and keeping published file sizes down etc… (see previous posts).

I am wondering what peoples experiences have been using the different image types while still maintaing the transparency (gif or png).

I am experiencing some weird things. It seems that whenever I use a .png Flash will still compress it the same regardless of size…

Example:

  1. create test flash page with nothing in it.
  2. import lo-res crap .png (40k); test movie; .swf file size = 20k
  3. import hi-res nice .png (200k); test movie; .swf file size = 20k

How is this possible?

Behavior is different with .gif’s.

Shed light anyone?