illumination

[Eric Den BREEJEN]

Hello grassusers,
I'm using the Spearfish database to try out some wildland fire risk mapping 
methods. For one of them I need to know the insolation. Does any one know a 
method to generate a illumination map using a given solar elevation angle ?
Thanks a lot, Moniek Vesseur.
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Name:  Eric den Breejen              x   Internet: breejen at cemef.cma.fr
Mail:  Ecole des Mines de Paris      x   Address : Ecole des Mines de Paris
       Cemef/IAM                     x             
       BP 207                        x
       06904 Sophia Antipolis cedex  x             
       France                        x             
Phone: ++33-93.95.74.86              x   Fax     : ++33-93.65.43.04
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