[Radiance-general] high reflectance & roughness metals

[Ignacio Munárriz]

hi, althought i guess it has been discussed already at the forum, i've
having some problems with high reflectance & roughness metals to simulate a
diffuse   metal (alluminium) garage door

my first atempt:

rpict -x 4000 -y 3000 -vf vistas/e3 -af ambext -ab 2 -ad 200 -as 30 -ar
300 -sj 1 -st 0 -dj .5 -pj .5 -t 60 exterior.oct>img/exteriore3.pic
pfilt -r .6 -x 800 -y 600 img/exteriore3.pic>img/exteriore3pf.pic

with the material
void metal jaimito_l_3dpgaraje
0
0
5 0.65 0.65 0.65 0.5 .1

and the result is
http://www.alfanature.com/avis/exteriore3b.jpg

as you can see there are some artifacts (horizontal bands) , are them due to
low-discrepancy?

the second attempt is using pure montecarlo

void texfunc metro
4 gloss_dx gloss_dy gloss_dz gloss.cal
0
3 .02 .02 .02
metro metal jaimito_l_3dpgaraje
0
0
5 0.65 0.65 0.65 0.5 0

and the result is
http://www.alfanature.com/avis/exteriore3.jpg

any way to improve that?
anyway i prefer pure montecarlo to default radiance, do you?
in other threads it was recommended to decrement sj and increment st, but
this isn't it a way to elude the problem?

thanks all