it's a tough call, but these days you want to give your surfers most options possible. if i can give you a suggestion, make sure that you have the clips in windows and mac formats since mac users want to download .mov videos - and your best friend is ffmpeg for doing that.
i would say go for the full length videos in high resolution and if you want to give also small videos, go for them in low resolution.
all in all for every video it will take 10x the hdd space if you want to have all options covered but that's what happens today if you want to be sure that you cover all thinkable options.
gab
|