Instructions to convert a MAP file to other formats

Convert to FITS

Use the AltWG toolset to get the proper format

Maplet2FITS --configFile fitsConfig_orex_spc.ini RAD201.MAP RAD201-fullv1.fits

An example ini file can be found here fitsConfig_spc.ini.
Notes from Ray Espiritu on 5 May 2020 about the ini file "It may look familiar as it has the same format as the nft config files you send me for generating MLNs. Format is KEYWORD#value. Notice that “//” denotes comment lines. This does not allow you to add custom keywords; the keyword has to exactly match a keyword that is normally populated in the fits header."
There will still be some header information you will want to change. For this use ChangeFitsHeader, also part of the AltWG distribution toolset.
More notes from Ray Espiritu on 5 May 2020 for "This tool allows you to add,delete, or modify keywords in the header. Run “ChangeFitsHeader –examples” to see examples for each operation (add, delete, modify, change). There is a limitation inherent in the fits format in that the new fits header cannot have a size difference of more than 2880 bytes from the old fits header. You shouldn’t encounter that if you are adding or deleting a handful of keywords."

Convert to GeoTIFF

First, convert to FITS format (and update headers as necessary).
Use GDAL to convert from FITS to GeoTIFF

gdal_translate -b 3 -a_srs RAD201-v5.prj -a_ullr -8510 8510 8510 -8510 RAD201-fullv1.fits RAD201-fullv1.tif

An example of the prj file can be found here, and can be viewed with a text editor such as "vi". RAD201-v5.prj
The -a_ullr is giving the bounds of the DTM in meters. The math is "Upperleft X = (Q*2+1) * GSD (in meters) / 2 * -1" and "UpperLeft Y = (Q*2+1) * GSD (in meters) / 2". So if the GSD is 20 m with a Q of 425, the math is (425*2+1) * 20 / 2 * -1 = -8510
The -a_scale option will tell the geoTiff how to convert the DN value to physical units. I am still working out how to determine the value needed.
If you are converting a fits file with multiple bands, you can specify a particular band with the -b <band #>
GDAL works with both fits and pgm
If your file has multiple bands, use the -b option to select a band

===Set proper values === This is still a work in progress, but I think this is close (21 Aug 2020). When you initially create the tif, the "values" will be in DN space and you will need to convert them to meters. You do this by setting the scale (multiplicative) and offset (additive), and then separately unscaling the pixels. You can't do these processes with one command line, you have to use two.

gdal_translate -a_srs INGV02_jrw.prj -a_scale 2.406482777E-03 -a_offset -3.627833373E+03 -a_ullr -4552.5 4552.5 4552.5 -4552.5 ING2EQ_DTM.pgm ING2EQ_DTMtemp.tif
gdal_translate -unscale -ot Float32 ING2EQ_DTMtemp.tif ING2EQ_DTM.tif

When using unscale, you also have to be sure you are output in the correct format, so use -ot for that.