# Invisible lights still visible throgh refraction

**URL:** <https://forums.chaos.com/t/invisible-lights-still-visible-throgh-refraction/51912>\
**Category:** Issues\
**Created:** [December 8, 2014, 11:12am UTC](https://forums.chaos.com/t/invisible-lights-still-visible-throgh-refraction/51912 "2014-12-08T11:12:53Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![kosso\_olli](https://avatars.discourse-cdn.com/v4/letter/k/dfb087/32.png) [@kosso\_olli](https://forums.chaos.com/u/kosso_olli)\
**Post date:** [December 8, 2014, 11:12am UTC](https://forums.chaos.com/t/invisible-lights-still-visible-throgh-refraction/51912/1 "2014-12-08T11:12:53Z")

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As the title says, I can see the lights behind my glass objects, even if they are set to invisble. They appear as black, completely blocking my background etc.  
EDIT: Also, they are appearing in the alpha channel behind these objects.

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**Author:** ![vlado](https://avatars.discourse-cdn.com/v4/letter/v/779978/32.png) [@vlado](https://forums.chaos.com/u/vlado)\
**Post date:** [December 8, 2014, 12:07pm UTC](https://forums.chaos.com/t/invisible-lights-still-visible-throgh-refraction/51912/2 "2014-12-08T12:07:59Z")

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Can you post a scene or send to [support@chaosgroup.com](mailto:support@chaosgroup.com) ? I can’t reproduce this here in a simple test, so there’s probably something else going on too.

Best regards,  
Vlado

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**Author:** ![kosso\_olli](https://avatars.discourse-cdn.com/v4/letter/k/dfb087/32.png) [@kosso\_olli](https://forums.chaos.com/u/kosso_olli)\
**Post date:** [December 8, 2014, 12:37pm UTC](https://forums.chaos.com/t/invisible-lights-still-visible-throgh-refraction/51912/3 "2014-12-08T12:37:43Z")

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Sure, here you go.  
I just found out that the problem has to do with the fog multiplier. Set it to zero, and the problem is gone. As soon as you raise it even slightly, to 0.01 for example, the light appears again. I can’t reproduce it with a simple scene though…  
[light\_prob.zip](https://forums.chaos.com/uploads/short-url/33aZOGfameNXf8tt2kS8FdnJdOc.zip) (83.6 KB)

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**Author:** ![ben\_hamburg](https://avatars.discourse-cdn.com/v4/letter/b/ba8739/32.png) [@ben\_hamburg](https://forums.chaos.com/u/ben_hamburg)\
**Post date:** [December 9, 2014, 11:44am UTC](https://forums.chaos.com/t/invisible-lights-still-visible-throgh-refraction/51912/4 "2014-12-09T11:44:42Z")

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hi there, I had a similar problem once. Turned outto be a problem with the transarency override. For optimization reasons I had it set to 2. Once I increased that value, the lights disappeared.

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**Author:** ![svetlozar.draganov](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/svetlozar.draganov/32/53004_2.png) [@svetlozar.draganov](https://forums.chaos.com/u/svetlozar.draganov)\
**Post date:** [December 9, 2014, 3:24pm UTC](https://forums.chaos.com/t/invisible-lights-still-visible-throgh-refraction/51912/5 "2014-12-09T15:24:24Z")

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> [@Charging for render nodes](https://forums.chaos.com/t/charging-for-render-nodes/46212/135):
>
> Sure, here you go.  
> I just found out that the problem has to do with the fog multiplier. Set it to zero, and the problem is gone. As soon as you raise it even slightly, to 0.01 for example, the light appears again. I can’t reproduce it with a simple scene though…

There is something wrong with the 3DSMax Camera here - everything works fine with VrayPhysicalCam.  
I’ll log this case into our system and I’ll let you know when we have some news about it.