Allows you to configure settings for saving a TIFF (Tagged Image File Format) image.
TIFF files can be compressed in a number of ways to reduce the file size. LZW (Lempel Ziv Welch) compression is the same method used in GIF images, and produces a significant reduction in file size without losing any image information (it is a lossless method). It should be noted that LZW compression is covered by a restrictive Unisys license.
PackBits compression is often used on Macintosh systems and is a form of Run Length Encoding (RLE) which, like LZW, is a lossless method.
Deflate compression, sometime known as "zip" compression, uses another variant of the LZW compression method and so gives similar results, but is not restricted by any licences. LZW compression should be used on logo-type images such as maps and line diagrams.
JPEG compression is the same compression methods used when saving JPEG files. JPEG compression should be used on photographs or realistic scenes.
Finally, you can leave the TIFF uncompressed for maximum quality, but be warned that file sizes can be very large.
As with JPEG (and some other formats) a comment can be added to the image up to 32KB. A default comment for new images can be set in Preferences.