Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] Bug Reporting => [Max] Resolved Bugs => Topic started by: MagicAlien on 2014-03-21, 20:59:48

Title: Corona light with directionality=1.0 - Noisy render
Post by: MagicAlien on 2014-03-21, 20:59:48

Hello to everyone, please exuse me if this is not a bug, but anyway it look weird to me.
I have this easy scene, with 3 CoronaLights: one of this lights is setted with directionality=1.0
Other general settings are defaults. Tested with alpha 5 and alpha 6 (the image below is from alpha 6).

(http://baugrafik.it/download/test_noise.jpg)

As you can see, is very noisy where the light is casting (also in the reflections). The noise increase directly proportional to the directionality value.

(http://baugrafik.it/download/test_noise_detail.jpg)

It converge to a decent solution only after ALOT of passes. High "Light samples multiplier" value does not help (now is 16 )
In attachment you can download the scene (3dsm 2014) if you'd like to give a try.

Title: Re: Corona light with directionality=1.0 - Noisy render
Post by: lhenix on 2014-03-22, 09:46:32

light normals,I think.....

add setting image,you can see different

Title: Re: Corona light with directionality=1.0 - Noisy render
Post by: lhenix on 2014-03-22, 10:14:44

I was download and tested,use 0.65 and get this image...

Title: Re: Corona light with directionality=1.0 - Noisy render
Post by: Ludvik Koutny on 2014-03-22, 12:07:34

Yeah. At the moment, rendering of lights with directionality is extremely inefficient. Just model a window, and put in CoronaSun. Then tweak shadow softness using size multiplier parameter of CoronaSun. It will give you similar result a lot faster.

Title: Re: Corona light with directionality=1.0 - Noisy render
Post by: MagicAlien on 2014-03-22, 13:06:02

Ok, thanks.
Actually it is a "projector simulation" and with the new circular shape would be a spot light simulation: I know that with the new alpha 6 we can use 3dsm standard light for that, but of course the final resaults are different fotometrically speaking.
Do you know if there are plans to fix this?

Title: Re: Corona light with directionality=1.0 - Noisy render
Post by: Ondra on 2014-03-22, 13:52:35

yep, I will try to fix it.

Title: Re: Corona light with directionality=1.0 - Noisy render
Post by: MagicAlien on 2014-03-22, 17:04:44

Quote from: Keymaster on 2014-03-22, 13:52:35

yep, I will try to fix it.

Great! And really congratulation (to all of you) for this great software, from the installation to the size, is a piece of art.

Title: Re: Corona light with directionality=1.0 - Noisy render
Post by: Ondra on 2014-03-29, 15:16:29

added to the list of known problems http://forum.corona-renderer.com/index.php?topic=102.msg543#msg543