Corona light with directionality=1.0 - Noisy render

[MagicAlien]

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).



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.



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.

[lhenix]

light normals,I think.....

add setting image,you can see different

[lhenix]

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

[Ludvik Koutny]

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.

[MagicAlien]

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?

[Ondra]

yep, I will try to fix it.

[MagicAlien]

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.

[Ondra]

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