Help for PHO_LAMBERT

PURPOSE:

This is the sub-menu associated with the Lambert photometric
function. This function needs just one input parameter (ALBEDO).


MATHEMATICAL BACKGROUND :

Lambert's law does provide a reasonably good descrition of the reflectance of 
high-albedo surfaces, like snow, but the approximation is poor for dark 
surfaces.

The Lambert's law is based on the empirical observation that the brightnessses 
of many surfaces are nearly independent of the emmission angle and azimuthal 
angle and on the fact that the brightness of any surface must be proportional 
to cos(incidence angle).

bidirectional reflectance [1/str] :

r(i,e,g)=A*cos(i)


PROGRAMMER:

Friedel Oschuetz
Institute of Planetary Exploration
DLR
12484 Berlin (FRG)

PARAMETERS: