Hi Devang, this is surprising because black is not even a color on the falsecolor palette. Can you post the HDR file and the radfiles generated prior to the Radiance run?
the black color is probably because of the maskThreshold. If you set it to 0 (default 0.1) you’ll see the purple pixels back in your image. I guess you probably know it already…
Now that doesn’t explain why the skylight is so dark with VLT=0.05 while it’s bright-ish compared to the scene with VLT=0.2 (I could replicate the issue on my machine).
I’ve tried replacing the glass material with a trans but that didn’t give me an answer.
This might be a version issue. I am using Radiance 5.2.91 dated 2018-06-20 (rcontrib -version on cmd). I am also running the perl version of falsecolor (the one shipped by NREL). Can you try a simple run to see if the parameters themselves are causing the error?
My rpict and falsecolor settings:
18:59:26 |mod:_radbase|func:call|msg:Trying to run: ['rpict', '-ab', '2', '-ad', '512', '-vf', 'view.vf', 'C:\\Users\\Sarith\\AppData\\Local\\Temp\\RAD_18_592h1dyfpp\\oconv_k93367ar.oct']
19:00:03 |mod:_radbase|func:call|msg:Trying to run: ['C:\\radiance\\perl\\bin\\perl.exe', 'c:\\radiance\\bin\\falsecolor.pl', '-i', 'test2.hdr']