KeyShot Forum

Technical discussions => General discussion => Topic started by: p3ngu1n on January 30, 2021, 06:04:56 PM

Title: Issue with rendering glossy surface?
Post by: p3ngu1n on January 30, 2021, 06:04:56 PM
Hey all, quick question regarding 0 roughness material.

I have a scene set up with physical lights. I'm trying to render a high gloss object and am finding that setting the "roughness" slider to "0" is creating a strange situation where the material no longer seems to reflect light.

Attaching some screenshots with various "roughness" settings.

I understand that no object is ever "perfectly" smooth, however, I have to wonder if this is expected behaviour?
Title: Re: Issue with rendering glossy surface?
Post by: Anindo Ghosh on January 30, 2021, 09:09:21 PM
With roughness set to 0, the size of the reflection is exactly the same size as the light source. A point source is a point, so the reflection would be infinitesimal, i.e. smaller than even a single pixel.

With a larger light source, I get a visible reflection even on zero roughness metals, please check if you have similar results.
Title: Re: Issue with rendering glossy surface?
Post by: p3ngu1n on January 30, 2021, 10:26:31 PM
That makes sense. If I throw an HDR light source it reflects just fine. Thanks!