I created an IES file with Easy IES. It's a 360 degrees omnidirectional and emitting equal intensities from all directions
For the Blender setup two point white light sources with 80 candela intensities (Luxcore IES Lights and Luxcore Point Source light) and each is situated at the center of two similar 100% matte hemisphere objects with radii of 1 meter. For rendering Total Path Depth is set to 1 to disable all indirect bounce lights inside the hemisphere.
After analyzing the results I found that the illuminances and luminances on both illuminated hemisphere objects are different. Checking the color values in the linear EXR file indicated that their luminances differ by a factor of around 12.6 and the Luxcore IES Lights illuminated hemisphere object dimmer than Luxcore point light illuminated hemisphere object.
Why do they differ despite both are set at the same intensities??? I also don't think the Lumen values in the IES file has any effect on the intensities as well.
BlendLuxCore IES Omnidirectional Point Source Doesn't Match Luxcore Point Source in Intensity
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BlendLuxCore IES Omnidirectional Point Source Doesn't Match Luxcore Point Source in Intensity
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Re: BlendLuxCore IES Omnidirectional Point Source Doesn't Match Luxcore Point Source in Intensity
Hi,
Interesting finding. Also the factor of 12.6 between the values is very close to 4*pi (full sphere solid angle). Is this coincidence?
Looking forward to the solution.
BR
Interesting finding. Also the factor of 12.6 between the values is very close to 4*pi (full sphere solid angle). Is this coincidence?
Looking forward to the solution.
BR
OS - Windows 7 X64
CPU - Intel CORE i7
GPU1 - Variants of notebook card from nVidia
GPU2 - Variants of notebook onboard card from Intel
Lux - Latest possible relaease
CPU - Intel CORE i7
GPU1 - Variants of notebook card from nVidia
GPU2 - Variants of notebook onboard card from Intel
Lux - Latest possible relaease
Re: BlendLuxCore IES Omnidirectional Point Source Doesn't Match Luxcore Point Source in Intensity
Hi,lighting_freak wrote: ↑Sun Mar 28, 2021 8:13 pm Hi,
Interesting finding. Also the factor of 12.6 between the values is very close to 4*pi (full sphere solid angle). Is this coincidence?
Looking forward to the solution.
BR
For me it's exactly 4*Pi if without noise.
Rendered with Irradiance Contour Lines 21 steps around 2 min 3 sec time: 12.6 x 80 candela = 1,008
12.56637 x 80 candela = 1,005.31
Thanks