[Radiance-general] rsensor/rcontrib

[Aris Tsangrassoulis]

Dear all,

trying to compare illuminance values on  a single point on the working  
surface located in the middle of a south facing room, three methods  
have been used (rtrace, rsensor and 3phase method using  
rsensor|rcontrib to estimate the view matrix) with the results  
difference been explainable. Sensor file represents spatial resonse  
file of a cosine corrected sensor.
When I have changed the sensor file with one having a narrow filed of  
view (2x10 degrees) illuminance value using the 3phase approach was  
the same (~1% difference) as in the case of the cosine corrected sensor.
The command was :
rsensor -h -rd 5000  -vf view_test.vf  narrow10.dat . |rcontrib   -c  
5000 -f klems_int.cal -bn Nkbins -b kbinS -m glazing -I+ -ab 11 -ad  
50000 -ds .1 -lw 1e-5 test_r.oct>narrow10.vmx

Repeating the calculation with rsensor command only (again narrow  
versus cosine corrected sensor file):

rsensor -h -rd 5000 -ab 5 -ad 2500 -ar 300 -aa 0.1 -i -vf view_test.vf  
narrow10.dat  overcast.oct|rcalc -e  
"$1=179*($1*0.265+$2*0.670+$3*0.065)">overcast_rsensor_10.dat

results differ 98%. Any hint would be appreciated.
I've examine the ray directions coming out from rsensor for both the  
sensor files and are in accordance with the spatial response. Using  
NREL's R4.2.a.4 on Windows.

Thanx,

Aris Tsangrassoulis