Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: lius86 on 2015-02-10, 12:03:44

Title: First time with Corona and..
Post by: lius86 on 2015-02-10, 12:03:44
Hello everyone,

I am 3D Visualizer, and I work for a company based in London. The last week I saw a presentation held by Peter Guthrie about The boundary, and i decided to have a try with Corona, for an interior scene.

The setup was really easy, as I just run the script for converting materials, adjusted a couple of them, and set up an hdri in the environment slot.

I sent the render keeping all the default settins, at 3000x2010 pixel of resolution, using a Xeon E5 2620 v2 , 2.10 GHZ and 32 gb of RAM, but after more than 10 hours, it was still full of noise.

I attached a 100% crop to show you.

I wanted to ask you guys, what I did wrong (if i did) and how to set up Corona for having decent render time.
I had the DOF activated on the Corona mod cam.

I have attached a screenshot of the corona buffer as well.

Thanks guys for your time and help!
Title: Re: First time with Corona and..
Post by: lius86 on 2015-02-10, 12:12:19
probably i should have posted in the help section...Can i be moved?

Sorry
Title: Re: First time with Corona and..
Post by: racoonart on 2015-02-10, 12:20:39
This may help you: https://coronarenderer.freshdesk.com/support/solutions/articles/5000501983 (https://coronarenderer.freshdesk.com/support/solutions/articles/5000501983)
In short:
- use portals
- you can try lowering msi (not to 0! ;) )
- you have quite low rays/s, is bitmap paging enabled? https://coronarenderer.freshdesk.com/support/solutions/articles/5000501981-rays-per-second-too-low (https://coronarenderer.freshdesk.com/support/solutions/articles/5000501981-rays-per-second-too-low)
Title: Re: First time with Corona and..
Post by: lius86 on 2015-02-10, 12:44:17
This may help you: https://coronarenderer.freshdesk.com/support/solutions/articles/5000501983 (https://coronarenderer.freshdesk.com/support/solutions/articles/5000501983)
In short:
- use portals
- you can try lowering msi (not to 0! ;) )
- you have quite low rays/s, is bitmap paging enabled? https://coronarenderer.freshdesk.com/support/solutions/articles/5000501981-rays-per-second-too-low (https://coronarenderer.freshdesk.com/support/solutions/articles/5000501981-rays-per-second-too-low)

Thanks, just added portals, decreased the MSI to 10, and de activated the bitmap paging..

I just sent a region crop, and i will put here the update.

Thanks
Title: Re: First time with Corona and..
Post by: lius86 on 2015-02-10, 13:16:36
This may help you: https://coronarenderer.freshdesk.com/support/solutions/articles/5000501983 (https://coronarenderer.freshdesk.com/support/solutions/articles/5000501983)
In short:
- use portals
- you can try lowering msi (not to 0! ;) )
- you have quite low rays/s, is bitmap paging enabled? https://coronarenderer.freshdesk.com/support/solutions/articles/5000501981-rays-per-second-too-low (https://coronarenderer.freshdesk.com/support/solutions/articles/5000501981-rays-per-second-too-low)

here a screenshot with the new settings.

What do you think?Still i bit noisy in my opinion.
The interesting thing (i guess) is that in the CESSENTIAL_direct pass, the noise is completely gone.

I did a test putting together the elements, and a quick PP, and the result looks great.
Hope to get one noise free...!
Title: Re: First time with Corona and..
Post by: lius86 on 2015-02-10, 13:38:50
Problem solved,

thanks a lot!
Title: Re: First time with Corona and..
Post by: racoonart on 2015-02-10, 13:39:21
Better, but your rays/s are still a low as before. After disabling Bitmap paging you have to save the scene and reopen it afterwards. If you don't do that it won't have any effect. You should have 3 or 4x as much rays/s after that.
Title: Re: First time with Corona and..
Post by: lius86 on 2015-02-10, 13:43:59
Better, but your rays/s are still a low as before. After disabling Bitmap paging you have to save the scene and reopen it afterwards. If you don't do that it won't have any effect. You should have 3 or 4x as much rays/s after that.

Thanks, did not do that!

Do you suggest to keep the MSI to 10, or doing different test, and trying to go back to 20?

Not sure what is best looking at this page: https://coronarenderer.freshdesk.com/support/solutions/articles/5000515636

Thanks
Title: Re: First time with Corona and..
Post by: racoonart on 2015-02-10, 13:47:47
Whatever is acceptable to you ;) Lower msi will lead to little less pronounced gi bounce from strong lights but will render faster. So if you don't see a difference, go with the lower value. If you want that extra bit of realism you will have to stay at 20 or even go higher (I never did that!)
Title: Re: First time with Corona and..
Post by: lius86 on 2015-02-10, 13:49:32
Whatever is acceptable to you ;) Lower msi will lead to little less pronounced gi bounce from strong lights but will render faster. So if you don't see a difference, go with the lower value. If you want that extra bit of realism you will have to stay at 20 or even go higher (I never did that!)

Sounds good,

I am really pleased with Corona, seems amazing!

edit: 2.500.000 of rays
and 2.600.000 actual rays
Title: Re: First time with Corona and..
Post by: maru on 2015-02-10, 16:01:37
This may be also helpful for understanding what decides about image quality (I hope so :) - any comments and critique on support system in general is welcome)
https://coronarenderer.freshdesk.com/support/solutions/articles/5000518064
Title: Re: First time with Corona and..
Post by: lius86 on 2015-02-10, 17:00:20
This may be also helpful for understanding what decides about image quality (I hope so :) - any comments and critique on support system in general is welcome)
https://coronarenderer.freshdesk.com/support/solutions/articles/5000518064

Hi Maru,

Thanks for the link. I read the article, and seems quite clear that the more amount of passes you do, the better the image.
But the question is : Why do I need to decide the number of passes before? i've never used progressive render, but what i would do is, launch the render, leave it rendering till i am not satisfied with the noise level.
How is your workflow using Corona?
Title: Re: First time with Corona and..
Post by: racoonart on 2015-02-10, 17:02:46
You don't need to decide anything. Leave passes at 0 and render as long as you wish. You can cancel / stop the render anytime you want.
Title: Re: First time with Corona and..
Post by: lius86 on 2015-02-10, 17:19:02
You don't need to decide anything. Leave passes at 0 and render as long as you wish. You can cancel / stop the render anytime you want.

yes exactly, so as long as the scene is done in the correct way (or in the way which you aim), the more you can wait the better it is.
Title: Re: First time with Corona and..
Post by: Fibonacci on 2015-02-11, 19:14:34
Hello,

just a bit trick...

If you use a bounce light in the scene, thet's helps a lot to the render engine to calculating. That's not matter what light you have, HDRI or Sky and Sun or other. Where the Sun light hit to the floor, just drop there CoronaLight ( with correct celvin and intensity), and that will help a LOT for computing.  Useally there has a strong noise where the light is not lit the scene correctly. Good solution to lighting thet area with low light setup.  ( Depend of the scene of course ). And if necessary after correcting the camera setup. The result is more clearer light passes.
If I have a problem with light noise, I always use this metode and I'm useing the 32/4 sampling balance. Ofcourse this is depend of how noisy the light passes and I have a correct albedo too.

Don't beleve it, just try it if you want. 
Title: Re: First time with Corona and..
Post by: maru on 2015-02-11, 19:49:39
Hello,

just a bit trick...

If you use a bounce light in the scene, thet's helps a lot to the render engine to calculating. That's not matter what light you have, HDRI or Sky and Sun or other. Where the Sun light hit to the floor, just drop there CoronaLight ( with correct celvin and intensity), and that will help a LOT for computing.  Useally there has a strong noise where the light is not lit the scene correctly. Good solution to lighting thet area with low light setup.  ( Depend of the scene of course ). And if necessary after correcting the camera setup. The result is more clearer light passes.
If I have a problem with light noise, I always use this metode and I'm useing the 32/4 sampling balance. Ofcourse this is depend of how noisy the light passes and I have a correct albedo too.

Don't beleve it, just try it if you want.
Noise is usually caused by randomly sampling bright and dark areas. This way you add more light to your scene and provide better direct sampling. But your scene won't be physically correct any more.
Title: Re: First time with Corona and..
Post by: Fibonacci on 2015-02-11, 21:31:45
Yes, your right Maru ! But when I have just a small window without enought light intensity ( I beleive the stronger HDRI multiplier is not the correct way to make more light in the scene) and lot of noise in the direct and indirect light (with pumped up samplings ), some softbox or bounce light helps a lot to lit the scene and in the result you can't really see it. Only dim light and helps to cleaning up the noise. Maybe not the physically best way, but like in the real photography help to lit and here help for the renderer. For the interiors - I beleive - it's not really matter.

Maybe I'm wrong...but ofcourse I have to check this new info. New for me.
https://coronarenderer.freshdesk.com/support/solutions/articles/5000518064

but, at this point that trick helped me a lot.