Light intensity

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Luximage
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Light intensity

Post by Luximage » Sun Jan 14, 2018 10:28 pm

I cannot increase or decrease the light intensity, it's fixed for all the lights, i have tried hdr, area light, plane with emission material, sun and sky, point, spot and hemi light.
Also the clamp output (render settings) that kills the fireflies doesn't seem to work.
I am on windows 7, blender 2.79
Here is my first image with the new Luxcore(pathcpu+sobol):

coor stool 2.jpg

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B.Y.O.B.
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Re: Light intensity

Post by B.Y.O.B. » Sun Jan 14, 2018 10:44 pm

Common mistake, what you can't change is the automatic tonemapper (it adjusts together with light intensity cancelling out your changes).
Implementing the imagepipeline is still on the todo list and has yet to happen.
Luximage wrote:
Sun Jan 14, 2018 10:28 pm
lso the clamp output (render settings) that kills the fireflies doesn't seem to work.
Which engine? Have you tried multiple values? You have to adjust the clamp value to the brightness of your lights. If you have very dim lights, you need a low clamp value.
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Dade
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Re: Light intensity

Post by Dade » Sun Jan 14, 2018 11:10 pm

BTW, LuxCoreUI has a simple procedure to estimate reasonable value for variance clamping:
https://github.com/LuxCoreRender/LuxCor ... w.cpp#L116

It is simply the average luminance of the rendered image multiplied * 10 (and than squared because we are talking of variance here). Intuitively, multiply the average luminance by 10 is like allowing a dynamic range of 10 in the rendering (the brighter pixel can be max. 10 times brighter than the average, this mean capping the intensity of fireflies).

BlendLuxCore could do the same, it can be done (on demand by pressing a button) during the rendering like it is done in LuxCoreUI or even during a view port rendering.
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Luximage
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Re: Light intensity

Post by Luximage » Mon Jan 15, 2018 10:47 pm

Thank you for the information Dade and B.Y.O.B.
The light is too dim so i had to lower a lot the clamping value, here is a result without the fireflies:

coord stool.jpg

Luximage
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Re: Light intensity

Post by Luximage » Mon Jan 15, 2018 10:51 pm

Also i want to ask if the clamp wrap in the imagemap node works?
I tried an example but it didn't work.

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Dade
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Re: Light intensity

Post by Dade » Mon Jan 15, 2018 11:00 pm

Luximage wrote:
Mon Jan 15, 2018 10:51 pm
Also i want to ask if the clamp wrap in the imagemap node works?
I tried an example but it didn't work.
Yes, I checked and it should be in v2.0Alpha1 (alpha1 has been released 7 days ago while the the wrap code has been written 12 days ago). B.Y.O.B, does it work for you ?
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B.Y.O.B.
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Re: Light intensity

Post by B.Y.O.B. » Mon Jan 15, 2018 11:08 pm

Yes, it works here:
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scrn_2018-01-16_00-07-43.png
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Luximage
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Re: Light intensity

Post by Luximage » Tue Jan 16, 2018 10:43 am

I was thinking to be able to do this with clamp, like it is in cycles (clip).
Cycles
cycles.jpg

Luxcore
Luxcore.jpg

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B.Y.O.B.
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Re: Light intensity

Post by B.Y.O.B. » Tue Jan 16, 2018 10:51 am

Clamp in LuxCore works like OpenGL's "CLAMP_TO_EDGE": https://open.gl/textures
However in your screenshot it looks like the texture is repeated. Maybe wait for the next alpha release.

If all border pixels of your texture are in Cyan, your result with LuxCore clamp should be the same like Cycles' "clip".
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Dade
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Re: Light intensity

Post by Dade » Tue Jan 16, 2018 11:41 am

Luximage wrote:
Tue Jan 16, 2018 10:43 am
I was thinking to be able to do this with clamp, like it is in cycles (clip).
Cycles

Luxcore
The LuxCore version looks like a repeat even if the UI says clamp, can you post the test scene ?
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