Summary:
    Fish-eye view multispectral sensor looking up at an altocumulus cloud field from the ground.

Included files:
    AC_lookup_RAD.bsq		MCScene radiance cube for no-clouds case
    AC_lookup_RAD.bsq.hdr	header file for above
    AC_lookup.bsq.OD		pixel LOS optical depth cube for clouds-present case
    AC_lookup.bsq.OD.hdr	header file for above
    Boreas5_avg.SRC_txt		average ground reflectance as a function of wavelength (nm)
    readme_AC_lookup.txt	this file
    
Scenario:
    Source reflectance data = AVIRIS data of Boreas, Saskatchewan, CAN, atmosphere removed with FLAASH, spectrally resampled to 5 custom bands
    nBands = 5
    first sensor band (chan, lambda, FWHM)=    1   440.    30. nm
    last sensor band (chan, lambda, FWHM)=    5  1020.    30. nm
    nxPixels = 511
    nyPixels = 511
    pixel LOS angles calculated from evenly spaced x & y direction cosines, dz2 = 1-dx2+dy2
    sensor view = fisheye up-looking
    SensorAlt (m) = 100.     
    SolarZenith (deg) = 5.     
    SolarAzimuth (deg) = 45.     
    DEM used = none, uniform 100 m elevation
    atmosphere model = MODTRAN mid-latitude winter
    aerosol model = MODTRAN rural
    sea level visibility at 550 nm = 23 km
    clouds = altocumulus cloud field generated by CSSM
    cloud fractional coverage = 50 %
    cloud scattering properties = MODTRAN cumulus
    cloud base altitude = 4 km
    max cloud thickness = 0.6 km
    max cloud OD at 550 nm = 5

Notes on pixel coordinates:
    The sensor LOS's are evenly spaced in dx and dy, the direction cosines in the x & y directions, and run from horizon to horizon. The LOS direction is specified as a unit vector, and so dz=sqrt(1-dx2+dy2). There are 511 x 511 pixels, and so dx and dy span the range -1 to 1 in steps of 1/255. For example, pixel(256, 256) lies in the center of the image where dx=dy=0 and dz=1. Pixel(511, 256) lies at right-center of the image where dx=1 and dy=dz=0.