Picture 53: 24Bit Color, File Format: Pnm - Image Access WideTEK 36 DS Manuals

The File Format defines the file format that is used to store a scanned document.
Note: There are some interdependencies between
That means, it is not possible to combine all color modes with all file formats.
For example, if an image is scanned in "24bit Color" it cannot be stored in
TIFF G4 file format.
Depending on the selected file format the control right beside can vary:
Some examples:
Picture 54: Binary, File Format: TIFF with G4 compression
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Picture 53: 24Bit Color, File Format: PNM

Color Mode and File Format.
Manual