I'm a little rusty but it comes down to the compression used & bitrate (how much information is used to represent each frame). Similar with say a TIFF vs JPEG image. They might be same number of pixels wide by deep but the jpg will be much smaller & probably poorer quality. Cojcolds Sent from my iPhone > On 28 Feb 2014, at 21:01, Paul Moortgat <paul.moortgat at pandora.be> wrote: > > I made (with my camera) a HD1080 movie of 11 minutes which was 1.5 GB large. > I downloaded a HD1080 movie of 45 minutes from Youtube which was around 750 MB large. > They both are in 1080. Why is there such a difference in size? They're both .mov files at the end. > Four times longer and half in size makes no sense to me. Mov is mov isn't it? > > Paul Moortgat > _______________________________________________ > X4U mailing list > X4U at listserver.themacintoshguy.com > http://listserver.themacintoshguy.com/mailman/listinfo/x4u