Would it make sense to add an option to the exposure map program to use the .MOI file to construct an exposure map?
The current .MOI file was created in much the same way as Steve's instrument maps (we think), and covers the same range as band 12. You can use the .MOI file, if you want -- just copy (or move) the .MOI file to a file called det_42_131_b.fits (if your observation was before Jan 25, 1991) or to a file called det_42_131_c.fits (if your observation was after this date). Then set the keyword imapdir (in the call statement) to the directory containing that file, and use band 12, e.g.:
IDL> spawn,'cp mydata/rp700015.moi mymaps/det_42_131_b.fits IDL> make_emap,1,expmap,totexp,emaphdr,imapdir='mymaps/' ? obseq=rp700015 ? dir=mydata/ ? band=12 ? end
The output will be written to the file rp700015_emap_42_131_b.fits.
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