That will be nearly impossible. Sorry, it's inherent in how any MPEG-based compression works and you can even see it on commercial DVDs and Blu-Rays. Fine high-frequency spatial noise is a quality killer as is combining completely static areas with moving ones. It will improve if you increase the output data rates at the cost of potentially getting choppy playback, but it will never go away completely. You would have to even out the motion, i.e. use an animated background, let your static elements move ever so slightly and potentially reduce the amount of rain.
I gave the settings I used in exporting the Adobe Photoshop CS5 video. I want to know how I should change my settings. I may be creating the video all wrong or using the wrong product. I had a photoshop file with layers. I wanted the rain to fall out of the sky, so i made a video with the raindropd falling at a tween of 20 and I had like 380 frames after that. I could figur out how to get another layer to move at a different pace, so I exported the video (many times until i could get it as clear as possible). Then i added the video back in, and added in another layer (the one that was floating in the sky). No matter which setting I used to export the video, it wasn't as crisp as I was looking for. I exported the video and iserted it back in for the movement across the bottom. That came out really clear (but it came from http://videoblocks.com). Do you or anyone else know which is the best settings for me to use in Photoshop CS5? Or is there another program i could use to makke clear videos?
I want the video to be as original as possible.