I am running CS4 and when I output to H264 with an output frame size of 720x480 in Encoder, the resulting file will be squished and played back at 640x480. The properties of the player show it is playing 720x480 and the video plays with black bars on either side. I never used to have this problem with earlier versions of Premier Pro. All of the settings (at least that I know of) in Premier Pro are set for 720x480. I used square pixels. Nothing seems to make much difference (although the square pixels made a little).
Playing back in Premier it looks great with it at 720x480. fills the playback window and no black bars on the sides. Its when it goes through Encoder that wierd things happen. I think I have tried about every variation of settings in encoder with not luck.
Start reading on PAR, pixel aspect ratio. 640 x 480 square pixels is equal to 720 x 480 with a PAR of 0.91.
Thanks Harm, that got me on the right track and solved the problem - right to the point!!!! Yahooo