Chaos Corona Forum

Chaos Corona for Cinema 4D => [C4D] General Discussion => Topic started by: ficdogg on 2018-04-12, 13:01:08

Title: Questions about portals and HDRi size
Post by: ficdogg on 2018-04-12, 13:01:08: I was wondering does the direction of the normals matter for portals?
Does the resolution of the HDRi play a role in direct illumination noise levels?
Title: Re: Questions about portals and HDRi size
Post by: maru on 2018-04-12, 14:27:11: Direction of normals does not matter for portals - we will be sure to add this info here: https://help.c4d.corona-renderer.com/support/solutions/articles/12000042132

As to HDRI resolution, it should not matter that much, but FAIK smaller resolution means slightly less noise.
Title: Re: Questions about portals and HDRi size
Post by: maru on 2018-04-12, 17:47:54: @Ben, the sunlight is from hdri?
Title: Re: Questions about portals and HDRi size
Post by: ficdogg on 2018-04-12, 18:30:27: Thanks, recently I was working on an interior render that was lit with only an HDRi and noticed that the ~~indirect~~direct illumination was quite noisy, so I'm just trying to troubleshoot it for future reference. Still, it rendered fairly fast at little over an hour to get it down to 5% noise level for 2304x1296
Title: Re: Questions about portals and HDRi size
Post by: Beanzvision on 2018-04-12, 18:51:23: Sorry, Scrap that last one, I left off the default shader. :\ 1K vs 16K (16 passes - no denoising)
Title: Re: Questions about portals and HDRi size
Post by: ficdogg on 2018-04-12, 19:41:22: Quote from: beanzvision on 2018-04-12, 18:51:23
Sorry, Scrap that last one, I left off the default shader. :\ 1K vs 16K (16 passes - no denoising)
Hmm, it does look like the high rez HDR produces slightly sharper sunlight. Out of curiosity can you post the indirect pass only as a reference?
Title: Re: Questions about portals and HDRi size
Post by: Beanzvision on 2018-04-12, 20:14:22: Yeah the sharpness is noticeable, even more so with a higher res render setting. Here are the indirect's
Title: Re: Questions about portals and HDRi size
Post by: Beanzvision on 2018-04-12, 20:14:56: Close up for fun :)
Title: Re: Questions about portals and HDRi size
Post by: ficdogg on 2018-04-12, 21:10:58: Interesting, I'll have to find some high rez HDRis and do some test renders to see how the render times change.
Title: Re: Questions about portals and HDRi size
Post by: Beanzvision on 2018-04-12, 21:37:34: The ones I use are from hdri haven ;)
Title: Re: Questions about portals and HDRi size
Post by: ficdogg on 2018-04-13, 11:41:51: Quote from: beanzvision on 2018-04-12, 21:37:34
The ones I use are from hdri haven ;)
Thanks that's a great site, didn't know about it.
Title: Re: Questions about portals and HDRi size
Post by: Eddoron on 2018-04-13, 14:12:03: Hi-res images obviously give a more detailed illumination. The question is: What do you need?
How large is the output? Do you want your HDRI to also serve as part of the scene? Do you need more diffuse shadows? etc.
There's a multitude of reasons for specific setups.
Also, don't forget that you can couple an HDRI with the sun object.