Specks of light when rendering interior

Total Posts: 1

Hello all,

When rendering an interior scene, I always end up with lots of specks of light where the sunlight hits an interior surface (in this case, the floor). I’ve attached a quick example. Settings used: quality level 10, Global Illumination, no auto exposure (exposure is at 0) and I’ve (of course) used skylight portals (on the outside of the window).
(The model is a simple example of the issue, but I’m working on a much larger model of a room where the issue is really distracting—I’ve attached an image of that room as well).

When I remove the skylight portal, the render becomes “grainy” but at least the sunlight hits the floor in a more realistic manner.

What am I doing wrong? Any suggestions?

Thanks in advance,


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Total Posts: 240

Hello Timothy,

Is it possible that your skylight portals are touching the window panes? If so, try moving the portals a millimetre or so away from the glass to see if that improves the results – there is an issue when two surfaces are in precisely the same place because it is essentially random which one the rays will hit first.

If that doesn’t help in your case, are you able to share your test model? You could either post a Dropbox (or similar) link here, or email it to us at

Shaderlight support