GI blotchies and splotchies

[Metin_7]

Hiya,

Can any of you experienced indoor renderers help me out how to get rid of these GI 'light leaks' (that's what we called them in my finalRender days) without sacrificing too much rendering speed...?



I've lowered the color and normal treshold and raised the third treshold (can't remember its name right now), tuned up the GI samples to 60 and left the interpolation at 20. The problem only occurs at sharp corners. You will probably recognize the problem. I guess this problem is different from the buggy harsh white spots that occur in non-cropped bitmaps (I didn't use any bitmaps in this scene). It looks more like a GI samples shortage problem in certain areas.

The light is a rectangular VRay light and the airplane windows are self-illuminated with tuned up Send GI.

Thanks in advance!

Cheers,

Metin

[UBIKmh]

The problem is related to one of the below mentioned facts:

>>The light is a rectangular VRay light and the airplane windows are self-illuminated with tuned up Send GI. <<


In the past I had some problems with self ilum objects in my scenes, I would render the scene without those airplane windows, and see the result


Second, if the other does not work..
Did you try higher VRay light sampling subdivs, slight increase in rendertime though

Or make a hole in your airplane roof and use skylight..

good luck,
Leon

[vlado]

Make sure your walls are not single planes but have some thickness; it may help.

Best regards,
Vlado

[Metin_7]

Thanks very much for your tips, Leon and Vlado. Leon, I've indeed turned down the VRay light samples a little ( to 8 ) and Vlado, the walls indeed have no thickness (the plane's hallway is in fact an extruded spline shape). I'll try out your tips and hope it helps.

Cheers,

/\/\etin

[TutanMark]

Make sure your walls are not single planes but have some thickness; it may help.

Hi Vlado,

When u have time, may i know (in theory), why the problem could be caused by object like that? (single plane) ... and not by object with thickness?


Thanks in advance
Marco

[Metin_7]

Yes, I'd be interested to know that too. It feels like having to use a certain amount of thickness because otherwise some light rays could leak through a single plane of polygons.

Cheers,

Metin