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View Full Version : Reflection gets brighter with more shading samples ?



madno
12-27-2015, 01:19 AM
Hi,

inspired by the caustics thread (here... (http://forums.newtek.com/showthread.php?149227-Caustics-in-Lightwave-2015-cont)) I played with my room test scene.
It is lit by an hdr as LW Textured Environment (no other lights used).
The surfaces are either Dielectric (glass and fluid) or Delta with different roughness settings (the non glass surfaces use blurred reflection).
GI is set to non interpolated Monte Carlo; Importance Sampling is on.

What I have noticed is, that the more Shading Samples I set, the brighter the reflected sun / sky and the caustics effect from the glass on the table becomes. Changing other values (e.g. RPE, Min. Max AA samples) does not have this effect.

Is this an expected behaviour?

131610

Sensei
12-27-2015, 02:28 AM
Your screen-shot looks good for me.

When samples are set to lower value, very few of them hit in that area, so they get blended with surrounding them pixels, giving impression it's lower brightness than normal. After enough rays is send, revealed is true brightness.

madno
12-27-2015, 05:20 AM
Hm,
but that would mean that going with low shading samples, like suggested in the manual, would always limit the reflection values.

131611

Anyway, at least I am now aware of this.