|MAPC2MAPC Help pages : Images
will load images as JPG, BMP, GIF, TIF and PNG. With MRSIDDecode
installed it will also read SID and JP2 files. With 7-zip installed it
will read Google Earth image overlays as KMZ or KML files (Garmin
Custom maps use this format, also). With GDAL installed, it will read all the formats supported by GDAL, including PDF and GEOPDF.
When Merging maps, the images may be of different types.
Images are held as their original bit depth but any Edit function that changes the image (other than crop) will force the image to a 24-bit depth.
When images have been altered (or files merged) the files are saved as PNG files with an option to reduce to 8-bit depth. For most maps, 8-bit depth saves a lot of space with no noticeable quality loss. Garmin Custom Maps are saved as JPG (within the KMZ); Trekbuddy tiles as PNG; Mobile Atlas in a variety of formats.
For a way to handle large TIF images see here.