light disappears lxs

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nigec
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light disappears lxs

Post by nigec »

TAO mentioned a problem with disappearing lights so I had a go
As you can see the spotlight disappears when there's an emitter
Also unrelated because an emitter can't be a null object I get these funky shadows
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B.Y.O.B.
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Re: light disappears lxs

Post by B.Y.O.B. »

You are using autolinear tonemapping. My guess is that the meshlight is so much stronger than the spotlight that it looks like the spotlight disappears when the tonemapper adapts to the brighter light.
Try to use a linear tonemapper and/or raise the spotlight gain.
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Re: light disappears lxs

Post by Dade »

B.Y.O.B. wrote: Thu Apr 25, 2019 10:03 am You are using autolinear tonemapping. My guess is that the meshlight is so much stronger than the spotlight that it looks like the spotlight disappears when the tonemapper adapts to the brighter light.
Try to use a linear tonemapper and/or raise the spotlight gain.
Yes and the mesh emission is astronomical high: 1000 gain, 100 power. Set gain to 1 and power to 1 (or increase the spot light gain) and you will see both (even with AUTOLINEAR tone mapping).
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nigec
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Re: light disappears lxs

Post by nigec »

Linear isn't working right in the plugin.. but I have to crank the spot up to about 1000 and the emitter 0.5.. ,maybe there's something screwy in the settings, the defaults are way to high obviously :oops:
auto Linear is a pain sometimes.. I just remembered I'd changed the plugin to use linear but when I put it on git I re did the original plugin so the changes could be seen, so I need to fix linear again

The funky shadow?
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Re: light disappears lxs

Post by Dade »

nigec wrote: Thu Apr 25, 2019 10:37 am The funky shadow?
Which one ?
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nigec
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Re: light disappears lxs

Post by nigec »

under the emitter, its a cross as if the light is emitting off the back faces of the emitter cube, I checked the cube and its only got front face materials
If you remember in Luxrender this would be a null object, but a null object doesn't emit light in luxcore, so I had to set it as matte
I've fixed the overzealous settings.. to be far I went into beta tester mode over TAO problem and not really thinking I could be adding my own bugs
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Re: light disappears lxs

Post by Dade »

nigec wrote: Thu Apr 25, 2019 12:08 pm under the emitter, its a cross as if the light is emitting off the back faces of the emitter cube
It is correct, diagonal sectors are lit by 2 side faces while the orthogonal one are lit only by one faces so the diagonal are brighter. Is that your were finding strange ?

Note: you can use a point light with radius (aka sphere light), instead of a cube, to get a nice uniform light source with penumbras.
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Re: light disappears lxs

Post by nigec »

Crazy thing is, in my render view I don't see the problem, but I've broke my render view so I'm not entirely sure what settings its using

Again I was looking at TAO issue, personally I would use a simple plane, even a triangle if I can.. as a Thea user a sphere would be a no no lol
I usually use emitters rather than point lights (again in Thea) point lights tend to be noisier and better in bias renders
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