m81_g.fits
TARGET  = 'M81     '           / target
EXPTIME =                 100. / exposure time (seconds)
FILTER  = ' (1) g (400-530)  ' / filter
DATE-OBS= '2012-04-07T04:08:44' / date of observation (UT)

m81_i.fits
TARGET  = 'M81     '           / target
EXPTIME =                 100. / exposure time (seconds)
FILTER  = ' (3) i (700-825)   ' / filter
DATE-OBS= '2012-04-07T04:37:38' / date of observation (UT)

m81_r.fits
TARGET  = 'M81     '           / target
EXPTIME =                 100. / exposure time (seconds)
FILTER  = ' (2) r (530-700)  ' / filter
DATE-OBS= '2012-04-07T04:27:45' / date of observation (UT)