[GRASSLIST:1166] (no subject)

[Andrzej Wroblewski]

Dear grass users

I have couple problems:

1. It's obvious that picture made from satelite in mountain terrain have different illumination of slopes.
That cause different pixel values on satellite image. 
Is in grass any function elimination that problem?

2. Haw to streach contrast in grass?

3. r.mapcalc
     >out=(ch3/ch1)*90
when complete writes:
min values 0, max values0
(ch1 and ch3 are my landsat band 1 and 3)
why? what's wrong?

I will appreciate your help

Best regards,

Andrzej Wroblewski