The longest dimension of any frame was 2048 - more importantly in width as I was projecting across 2 screens. All of the Logos I was using were landscape. I find that if I go with the highest resolution it gives me more versatility with slow zooms and pans across the image.

Some files were the full 2048 x 2048 whereas others were 2048 x 768.

A quicktime with 18 different images in it was only about 6-8MB with each logo taking up the default 12 sec. This was far more efficient than the original photshop files with their layering. The main thing was having to do a save as with layers switched off in Photoshop if you want to keep layer styles like drop shadows.

Cheers

Toby