Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: Benjanowitz on 2016-03-01, 23:51:13

Title: Noise problem (HDRI Lighting, Interior scene)
Post by: Benjanowitz on 2016-03-01, 23:51:13
Hey guys,
a real corona noob here.
I'm starting using Corona with Cinema 4D R15.
Trying to replicate a Vray scene of my own, to compare render times and, of course, quality.
I'm having big issues to get a nice, well lit scene, noise-free.

I'm still at  the override-material-basic-state.

So my two scense have these settings:

VRay:
Camera:
ISO: 100
F-stop: 1.8
Shutter speed: 60

Light:
HDRI Dome light: 1433 Sun Blue Sky from PG. Intensity 4, Gamma corrected at 0.65

Default vray override mtl.
600x450

Corona Render:
Camera: (with the corona camera tag)
ISO: 100
F-stop: 1.8
Shutter speed: 60

Light:
C4D Sky (with no corona sky tag) + corona mtl with same HDR text on the diffuse (tryied on the emission also) with a filter and gamma corrected at 0.65. Intensity? How do I control that?

Render Settings:
Stolen straight from the Interior scene sample.

General Settings:
Pass limit: 9999
GI: Path Tracing + UHD cache

Exposure and Color mapping:
Use photographic exposure.
Same settings as the corona camera tag.

Performance:
Lock sampling pattern.
GI/AA: 32
MSI: 200
Light samples multiplayer: 2
Max ray depth: 25

No materials in the scene.
600x450.
Of course there are no glasses at the windows, same rotations for the HDRI.


The corona render is way too darker and super noisey (can't really see it in this low-pixel version, but it's really really noisey)
How do I solve it?
Thanks again guys.

Ben.





Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: maru on 2016-03-02, 12:47:37
I think you should use Corona sky for the lighting. Another idea is to crank up exposure until you get desired brightness. Any chance you could share the scene, or some simplified version of it?
Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: Benjanowitz on 2016-03-02, 13:54:15
Hi and thanks for your reply. Unfortunately I can't provide you the scene cause it's a mix of bertrand benoot models that he sells.
So thriugh the corona sky I might be able to crank the exposure of my hdri up? The noise that I get will disappear?
Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: maru on 2016-03-02, 14:20:02
Quote
Hi and thanks for your reply. Unfortunately I can't provide you the scene cause it's a mix of bertrand benoot models that he sells.
Can you send the light+camera+render settings setup only, without the models?

Quote
So thriugh the corona sky I might be able to crank the exposure of my hdri up? The noise that I get will disappear?
No. You should be able to either use Corona Sky and have correct brightness, or crank up exposure and make the rendering brighter without changing the intensity of the HDR.
Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: Benjanowitz on 2016-03-02, 19:38:15
Thanks again for the support.
camera, lights and render settings are posted here in the first post!
I added a corona sky tag and set the multiplayer to 15 and is still dark. Plus I think that now my HDRI it's not lighting the scene.
Still dark and super noise!!
Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: 4b4 on 2016-03-02, 21:45:45
Hi Ben

I've just tried out your cam settings with the corona sky and corona sun and it's working fine.

Have you got the use photographic exposure box ticked?



Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: Benjanowitz on 2016-03-02, 22:03:36
Yes, I did it...
Too many doubts guys and I can't find clear answers.

HDRI text in diffusion or emission channel?
For mimic the "Vray intensity" of light (in my case was 4) what parameter should I trick?
Should I use the c4d sky with or without the corona sky tag?

And why I still getting so much noise?? Even if I crank the light up (surely in the wrong way!)
Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: NicoB on 2016-03-02, 22:54:34
Hej Benjanowitz,

You are getting frustrated :(
That's not good, because I'm absolutely sure
you just miss something really simple.

You will be happy with corona once you figured out
hier to use it. Remember starting Vray?
It's always that little curve at start.

So please hand just the empty space of your scene over to us,
so we are alle to help.

You can delete everything but walls and setup.
I will help you tommorow morning at first.

I'm sure we can help.

In some testing I had absolute great results with corona in c4d.

So, all the best and looking forward helping you.

Nico
Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: Benjanowitz on 2016-03-02, 23:02:02
Wow thanks for the kind words nico!
So I'll provide you guys withe the empty scene (just the walls, camera, lights and settings)
Do I have to include also the HDRI? It's from Peter Guthrie Pack 1433.
Thanks!!
Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: NicoB on 2016-03-02, 23:11:20
..ok great.
Sorry for the autocorrect from my phone :)

I would'nt recommend sending the PG Hdri file.
Someone won't be happy about it ;)

Maybe you could send a PM with one free HDR file in your scene.
(I dont think your problem is linked to the Hdr, so it should not matter).

So, let's see and win tommorow :)

Greetings
Nico
Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: Benjanowitz on 2016-03-02, 23:20:11
Yea, you're right.
The problem is also with the scene. I've removed everything from it, except the ceilings, floor, walls and camera. But the whole scene is from Bertrand Benoit (Baron Haussmann), wich I bought it few months ago.
What should I do? Should I upload it here? Mmmh...
Thanks again!
Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: NicoB on 2016-03-03, 07:41:36
Hej Ben,

I dont think it´s also linked to geometry in your scene.
(Because you mentioned to have no glass in windows)

To get forward:
Delete the HDRI and the geometry from your scene and
just build or load something else like an interior and one free HDRI from free sources.
(I think it´s because of settings, so you should get your result even with other basic scene setups).

All the best
Nico
Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: 4b4 on 2016-03-03, 09:57:16
Hey Ben

It's worth sticking with it. Bear in mind it's still in alpha so it's a bit rough round the edges in places but people are churning out some really good work in it already using C4D.

To answer some of your questions:

If you want to use an HDRI put it in the diffuse channel only. You can apply this to a sky object or there are some options within the scene environment tab of render settings.

For now I'd just use the Corona Sky and Corona Sun. Corona Sky is the C4D sky object with a corona sky tag (this excellent work gives you an idea of what you can do with it: https://forum.corona-renderer.com/index.php/topic,11102.msg70913.html#msg70913 (https://forum.corona-renderer.com/index.php/topic,11102.msg70913.html#msg70913) )
Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: Benjanowitz on 2016-03-03, 11:05:41
Hej Ben,

I dont think it´s also linked to geometry in your scene.
(Because you mentioned to have no glass in windows)

To get forward:
Delete the HDRI and the geometry from your scene and
just build or load something else like an interior and one free HDRI from free sources.
(I think it´s because of settings, so you should get your result even with other basic scene setups).

All the best
Nico

Ok, so I'll upload the semi empty scene as you suggested me!
It's so weird because I've used the same render setting as the corona testing scene!
Thanks again!

Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: Benjanowitz on 2016-03-03, 11:10:39
Hey Ben

It's worth sticking with it. Bear in mind it's still in alpha so it's a bit rough round the edges in places but people are churning out some really good work in it already using C4D.

To answer some of your questions:

If you want to use an HDRI put it in the diffuse channel only. You can apply this to a sky object or there are some options within the scene environment tab of render settings.

For now I'd just use the Corona Sky and Corona Sun. Corona Sky is the C4D sky object with a corona sky tag (this excellent work gives you an idea of what you can do with it: https://forum.corona-renderer.com/index.php/topic,11102.msg70913.html#msg70913 (https://forum.corona-renderer.com/index.php/topic,11102.msg70913.html#msg70913) )

I totally want to stick with corona!! Yes, it's still really buggy...When I copy and paste a text from a channel to another, it crashes! Really annoying! But the results I've seen are amazing!
I really love Vray, but the rendering times are very frustrating! Even with the scene optimization theory from the one and only Grant Warwick!
Speaking of Grant, is there in Corona a way to imitate his falloff method??
Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: maru on 2016-03-03, 13:15:35
I can confirm that the proper method is sky object + Corona's standard texture tag with the map loaded as diffuse color. (without Corona sky tag)
Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: Benjanowitz on 2016-03-03, 13:36:26
Ok!
And what about the intensity? Is the Exposure? If I have 4 of intensity power in vray, should I put 4 in the exposure? Mmmh...
Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: maru on 2016-03-03, 14:19:10
You can either increase exposure in Corona render settings, or in the shader. This will have the same effect if there are no other light sources.
Title: Re: Noise problem (HDRI Lighting, Interior scene)
Post by: Benjanowitz on 2016-03-03, 14:52:41
Ok, but what about if I use the photographic exposure? If i increase the exposure of the HDRI in the diffuse channel I get a burned out background that I can't correct through the color mapping!