Not only did I ask the wrong question but I was standing in the wrong place and looking in the wrong direction.......
Well that is what I was told when I put my question to a friend of a friend on playing .avi files on iPads, [see earlier post]. It seems that iTunes acts as a 'conduit' through which you pass your files and they become 'movies' and can then be synced with your iPad and played.
I then found that it is best to export files from Prem Pro in .mp4 format using the iPod/iPhone presets under H264.Start up iTunes and import the .mp4 file to the Library and then drag from the Library to the iPad and it goes through a 'conversion' and appears in the Video Library on the iPad and plays.
I'm still testing but some of the files auto fill the screen on the vertical dimension of the movie (it is not a video anymore!!! apparently) but double tapping screen changes the auto fill to the horizontal dimension. I even emailed some test files and they play on iPhones. Progress?
I can live with this but why can't you import all variants of .avi files? Those exported from PP will not go into iTunes.
Enough for today, I hear you say!
Gerry