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Yes, this question, again.
In Max VrayLightMtl documentation, we can read:
"If you know the photometric power of a self-illuminated object in lumens (e.g. 1700 lm for a 100-watt bulb) you can calculate the multiplier for VRayLightMtl if you divide the lumens by the surface area of the object in meters (the 3ds Max Measure utility can be used for this), provided that the self-illuminated color is pure white."
A little bulb could have, around 10 squared centimeters, so, in meters would be 0.001 squared meters. 1700 lumens / 0.001 would be an intensity of 1700000. If we apply this material at that object, inside a cube doing as "room", use physical camera, fstop at 2.8, iso at 200, shutter speed at 60 (should be fine for expose with a 100 watts bulb, right?), the render result is a totally white render. With an intensity of 500-1000 render would be correct, but then, how is the correct formula?.
Knowing that in Maya, we must keep scene in cm units, for a correct behaviour of IES lights (leaving the intensity at 1 to get the waited result), then, here in Maya, still we need measure the radiant surface in Squared Meters?, Or we need do it in Squared Centimenters?. 1700 lumens / 10 = 170. But this appears be not enough, so, I still am confused about this issue.
What am I doing wrong?.
Any way to radiate photons from a VrayLightMtl?
In Max VrayLightMtl documentation, we can read:
"If you know the photometric power of a self-illuminated object in lumens (e.g. 1700 lm for a 100-watt bulb) you can calculate the multiplier for VRayLightMtl if you divide the lumens by the surface area of the object in meters (the 3ds Max Measure utility can be used for this), provided that the self-illuminated color is pure white."
A little bulb could have, around 10 squared centimeters, so, in meters would be 0.001 squared meters. 1700 lumens / 0.001 would be an intensity of 1700000. If we apply this material at that object, inside a cube doing as "room", use physical camera, fstop at 2.8, iso at 200, shutter speed at 60 (should be fine for expose with a 100 watts bulb, right?), the render result is a totally white render. With an intensity of 500-1000 render would be correct, but then, how is the correct formula?.
Knowing that in Maya, we must keep scene in cm units, for a correct behaviour of IES lights (leaving the intensity at 1 to get the waited result), then, here in Maya, still we need measure the radiant surface in Squared Meters?, Or we need do it in Squared Centimenters?. 1700 lumens / 10 = 170. But this appears be not enough, so, I still am confused about this issue.
What am I doing wrong?.
Any way to radiate photons from a VrayLightMtl?
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