I appear to be getting false illumination when rendering through multiple panes of glass into a shaded space... Render settings are the default Outdoor Daylight Fast settings with the Ray Threshold increased to 10.
That is a door and the containing wall inside the room viewed through a balustrade and a window. On a view that looks over the balustrade, the interior is essentially black due to the lack of interior illumination.
A different location using the default "Outdoor Daylight Fast (Physyical)" settings.
Lingwisyer wrote: Ray Depth is 10, enough for 3 layers of glass. Lowering the Ray Threshold does not change the result.
That might not be enough. I just did a quick test here, and actually lowering ray threshold did more for me. Try setting the Ray Threshold to 1% and the Ray Depth to 30. If that doesn't solve your problem, it is possible that it's a limitation of the rendering engine, or there's something else in the way. In this case please send me the project in a Private message (in a PLA format), so that I can investigate it further!
Daniel Alexander Kovacs
Professional Services Consultant
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