I save in .tiff format in rgb color "convension". CMYK is almost exclusively used as a color convention when you want your image printed in a professinal print house. If you have saved your image in a .tiff format, the correct color information will be stored with your picture, and either you or the print house can do the conversion to CMYK. So bottom line; unless you want a professional print of your image; don't worry 'bout it. :) Britt