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I need help with my glass material. For some reason when I add glass to my scene it makes these little dots which I can´t get rid of.

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This is the node editor for my glass material.

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    $\begingroup$ These are called fireflies and there are multiple techniques on how to remove them. I'm sorry if my answer isn't really helpful as I'm also a beginner at Blender. Here is an article by Blender Guru. $\endgroup$ – Lee Aug 19 '18 at 17:23
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If your glass is always just planar and you don't need to use refraction for artistic reasons (all the light that enters your glass just goes to the other side in a parallel fashion, or gets reflected), then you can replace the Glass material with a material that is mostly transparent, but reflects at extreme angles:

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"flat" glass material

when you use this material, your window needs to be just a plane, not a solid.

These are the two options compared: a) glass shader on a solid window, b) "flat" glass material (see above) on a flat (2D) window.

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As you can see, reducing the unnecessary light path calculations "through the glass" makes the render less noisy.

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  • $\begingroup$ Thank you, fortunately I was using flat 2D planes so I was able to use this material and it looks good:) $\endgroup$ – daniel_a123 Aug 20 '18 at 10:47
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Glass is prone to do that; those dots are technically called "fireflies". For your shader, I suggest adding volume effects, like volume absorption, to handle the inside of the glass, as typical shades only work with the surface without them (and actual glass is very volumetric). The rest of it is an artifact of ray casting, which you can typically get around by increasing the size of your light source, or lowering its intensity.

Another possibility, if none of that helps enough, is to go to your rendering settings and reduce the number of bounces. Good luck!

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    $\begingroup$ Instead of just increasing the size of the light I increased the size of everything and It worked just fine (I´ve read somewhere that it´s harder for the shader to calculate light and shade on smaller objects). Thank you for your help!:) $\endgroup$ – daniel_a123 Aug 20 '18 at 10:45

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