# V-Ray Disc light problem

**URL:** <https://forums.chaos.com/t/v-ray-disc-light-problem/52081>\
**Category:** Issues\
**Created:** [December 22, 2014, 1:29am UTC](https://forums.chaos.com/t/v-ray-disc-light-problem/52081 "2014-12-22T01:29:38Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![Syclone1](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/syclone1/32/6794_2.png) [@Syclone1](https://forums.chaos.com/u/Syclone1)\
**Post date:** [December 22, 2014, 1:29am UTC](https://forums.chaos.com/t/v-ray-disc-light-problem/52081/1 "2014-12-22T01:29:38Z")

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Not sure if this is just with the Disk light as I haven’t tested it yet and not sure if its a bug or not but this strikes me as strange none the less. When using the “Directional” settings under “Rectangle Light options” at 0.0 it renders as expected and can see the light as white in the rendering but as you increase the parameter the light goes from white at 0.0 to black at 1.0

-dave

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**Author:** ![matanov](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/matanov/32/21656_2.png) [@matanov](https://forums.chaos.com/u/matanov)\
**Post date:** [December 22, 2014, 8:11am UTC](https://forums.chaos.com/t/v-ray-disc-light-problem/52081/2 "2014-12-22T08:11:08Z")

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If you mean that the actual light (as geometry) is rendered black when directional is 1.0 (or near), it is completely normal.

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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 22, 2014, 8:27am UTC](https://forums.chaos.com/t/v-ray-disc-light-problem/52081/3 "2014-12-22T08:27:11Z")

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If this is the problem, it happens with rectangle lights as well; the light actually needs another parameter in addition to the directionality, that specifies what percentage of the light is directional (with the remaining light being diffuse like normal).

Best regards,  
Vlado

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**Author:** ![Syclone1](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/syclone1/32/6794_2.png) [@Syclone1](https://forums.chaos.com/u/Syclone1)\
**Post date:** [December 22, 2014, 2:01pm UTC](https://forums.chaos.com/t/v-ray-disc-light-problem/52081/4 "2014-12-22T14:01:28Z")

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> [@svetlozar.draganov](#):
>
> If you mean that the actual light (as geometry) is rendered black when directional is 1.0 (or near), it is completely normal.

This is exactly what I mean, good to know thank you. I was hoping this was not normal but Ill just go back to using self illum objects to fake the bulbs 🙂

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**Author:** ![Brendan\_Coyle](https://avatars.discourse-cdn.com/v4/letter/b/e99b99/32.png) [@Brendan\_Coyle](https://forums.chaos.com/u/Brendan_Coyle)\
**Post date:** [December 22, 2014, 2:57pm UTC](https://forums.chaos.com/t/v-ray-disc-light-problem/52081/5 "2014-12-22T14:57:57Z")

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dug this up again, [http://forums.chaosgroup.com/showthread.php?54158-circular-plane-light&p=622034#post622034](http://forums.chaosgroup.com/showthread.php?54158-circular-plane-light&p=622034#post622034)