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UltraViolet
06-08-2010, 10:58 AM
Hello guys ...

I have a very simple test scene (see render below) where small beveled corners look too bright.

Is this behavior normal (somehow it looks wrong to me, like that area is not occluded properly or something), am I doing something wrong (bad geometry perhaps) or is this limitation of GI solution itself ?

Scene file included :)

Hieron
06-08-2010, 05:36 PM
Those bevelled polygons are more perpendicular to the majority of the incoming light in such corners and thus light up more. So I guess it is "correct". Just turn off GI and check the bevel in the lowerleft. Same thing.

UltraViolet
06-08-2010, 06:07 PM
Those bevelled polygons are more perpendicular to the majority of the incoming light in such corners and thus light up more...

Thanks for replying ...

Lol, well, yeah, that sounds logical, but still, for some stupid reason, when I look at the render itself, it does not look "correct" (enough) :)

accom
06-09-2010, 01:01 AM
Actually - if I look arround my office, corners in particulary, it look just the same!

3DGFXStudios
06-09-2010, 03:04 AM
You can turn of transparency and volumetric rays and directional rays in your settings. The beveled edges that appear lighter is normal like Hieron said.

3dworks
06-09-2010, 06:48 AM
Hello guys ...

I have a very simple test scene (see render below) where small beveled corners look too bright.

Is this behavior normal (somehow it looks wrong to me, like that area is not occluded properly or something), am I doing something wrong (bad geometry perhaps) or is this limitation of GI solution itself ?

Scene file included :)

open in photoshop and observe the RGB values when pointing with the mouse at those areas. you can read out the actual pixel values and see that those seem to be consistent overall...

our brain is easily tricked by shapes and contrasts, all optical illusions are based on those and on how we perceive 3d space.

cheers

markus

Hieron
06-09-2010, 07:49 AM
Nah, the edges are clearly brighter by about 5 to 10 on all channels. 5 to 10 seem little but it is easy to see by eye.

And it is as it should be. Don't think you can compare with a real world room as I highly doubt that real world room would have a single "bevel" of that big size and flat shape. Make the bevel smaller and more round and it is way less noticable.

UnCommonGrafx
06-09-2010, 08:12 AM
I am learning to UNDO that behavior: make things bigly and noticeable and then wonder why it isn't subtle. haha. Lol at self...

Wood grain is a biggie. My wife helped to straighten me out on that.
Hieron says it well. Only buildings i've seen it that big is in older buildings, prior to 1940. Industrial buildings, mostly, whose windows were framed of concrete. At least the sill leading up to the window.

All is right in your scene. Modeling... maybe not done.