KeyShot Forum

Technical discussions => Materials => Topic started by: SamuelBedin on October 04, 2017, 08:41:35 AM

Title: Black spots on cloudy plastic
Post by: SamuelBedin on October 04, 2017, 08:41:35 AM
Hi to all, I'm on Mac OS machine and I'm using keyshot 7.0.456 and I'm using a floating licence at my University. I'm trying to render the new cloudy plastic from keyshot 7, the problem is that when the render is done I see all these black spots on the plastic material. It seems that when the cylinder (as you can see in the picture) has another object inside these black spots are generated. I tried to change ray bounces from 6 up to 35 with a slight improvement, global illumination, transparency distance from 0,5mm up to 10mm, scale the model inside the cylinder but nothing of this solved completely my problem. Any idea of what I am doing wrong?

Attached you can find the ksp file. Thank you in advance
Title: Re: Black spots on cloudy plastic
Post by: guest84672 on October 04, 2017, 11:42:50 AM
I grabbed your scene and opened it, and rendered it using Max Samples set to 256. Does this look correct?
Title: Re: Black spots on cloudy plastic
Post by: SamuelBedin on October 05, 2017, 03:23:14 AM
Hey thank you, yes it looks perfect!! so it's just a matter of samples ? I didn't tried to max them out  because of time issues. No chance that there are other reasons behind this problem ? thank a lot again
Title: Re: Black spots on cloudy plastic
Post by: DMerz III on October 05, 2017, 07:17:25 AM
Sample rate, but also curious if you're using Product Lighting Mode or Interior Lighting Mode. I think Thomas might be using the Interior mode? Might make a difference.
Title: Re: Black spots on cloudy plastic
Post by: guest84672 on October 05, 2017, 03:45:54 PM
No I didn't change a thing - left at the product lighting mode. Just switched to Max Samples mode and cranked up the samples to 256.

@SamuelBedin, yes only samples. But make sure to switch to Max Samples Model. Cloudy plastic can take a little longer to calculate. It is, after all, a complex material with lots of calculations going on.

Max Samples render mode is the way to go. Gives you the most consistent results (most of the time).
Title: Re: Black spots on cloudy plastic
Post by: SamuelBedin on October 06, 2017, 06:09:31 AM
Quote from: thomasteger on October 05, 2017, 03:45:54 PM
No I didn't change a thing - left at the product lighting mode. Just switched to Max Samples mode and cranked up the samples to 256.

@SamuelBedin, yes only samples. But make sure to switch to Max Samples Model. Cloudy plastic can take a little longer to calculate. It is, after all, a complex material with lots of calculations going on.

Max Samples render mode is the way to go. Gives you the most consistent results (most of the time).

Perfect, thank you so much!
Title: Re: Black spots on cloudy plastic
Post by: DMerz III on October 06, 2017, 07:16:36 AM
 :) thanks for clarifying Thomas!