Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: Simonlp on 2019-11-15, 21:24:58

Title: Corona Light Portals - Setup
Post by: Simonlp on 2019-11-15, 21:24:58
Hello Forum

I have a question regarding Corona Light Portals.

I experienced fairly long render times in this particular scene, so I wanted to decrease render time. Obviously one solution was to add light portals to every window. As you can see in my scene the windows are divided into several parts and is not just one big opening as we see with many demonstrations of light portals in effect. (On the Corona Freshdesk site for example.)

So my question is; how would you set up the portals to work effectively? Because I don't seem to get a lot of benefit from using them. My setup is I use one portal for every opening. Would it be better if I made a light portal for every single small divided part of the window, or should one light portal for the entire opening be enough?

Also see my "beautiful" illustration to better understand the issue.
Title: Re: Corona Light Portals - Setup
Post by: romullus on 2019-11-15, 21:49:07
I alwats do A variant. I didn't do any comparisons to B, but if anything, it's much easier to set-up.
Title: Re: Corona Light Portals - Setup
Post by: Simonlp on 2019-11-15, 21:54:39
It's true, it's way easier to do A, that's also why I went with it. I was hoping someone on this forum would have experience with it, because it almost seems like A makes no difference compared to using no light portals.
Title: Re: Corona Light Portals - Setup
Post by: romullus on 2019-11-15, 23:22:48
Some scenes just don't have benefit from portals, some gets even noisier with portals than without. Portals are not silver bullet, if you see that they doesn't help, then there's no point to use them. Just delete and forget :]
Title: Re: Corona Light Portals - Setup
Post by: Simonlp on 2019-11-15, 23:24:59
Fair point. I will keep that in mind in the future, thank you for the suggestion :-)
Title: Re: Corona Light Portals - Setup
Post by: lupaz on 2019-11-16, 02:46:36
It's true, it's way easier to do A, that's also why I went with it. I was hoping someone on this forum would have experience with it, because it almost seems like A makes no difference compared to using no light portals.

Since a few versions ago I feel that portals have no effect whatsoever. No matter what scenario. It’s a waste of time as far as I can tell.
Title: Re: Corona Light Portals - Setup
Post by: maru on 2019-11-18, 16:59:23
According to various investigations, those two variants should give more or less the same results (depending on the specific setup, lighting, etc). So using A is usually easier.


Since a few versions ago I feel that portals have no effect whatsoever. No matter what scenario. It’s a waste of time as far as I can tell.
This shouldn't be true, at least for small windows.