the tiff format is signifagantly larger then Jpg (for example a recent image I did at 2000x2000 was just over 11 megs in Tiff and around 350K in Jpg at 20% compression) but you will ultmately create vastly better printed images from Tiff files. and there is no degridation in repeated saving versus the marked degridation caused by just one resave in Jpg.