Grain in rendering

[THAMIN]

I am very new to corona rendering and loved this interactive...
Please advice what is the cause of this grain texture and how to remove it

[Beanzvision]

Hi there, can you share more details about your render settings? Do you have denoising enabled at all? If not, this can be turned on via the render settings. I see that you also have strong sunlight being scattered across various areas which may be the cause of this.
https://support.chaos.com/hc/en-us/articles/4528588388113-How-to-use-denoising-in-Corona-for-3ds-Max-

[THAMIN]

Thank you for advice Beanzvision,

Changed the settings to

Render size 5000 x 3000
Denoiser is set to Corona High quality, Radius 1
Pass 3
Noise Level 3
Environment : Single map corona sky

Still I haven't get Sharp edges for detailing in view

[James Vella]

I wouldnt go over a denoise of 0.65, 1 is too blurry.

Noise level of 3 should be ok, pass level should be much higher, minimum of 75 in my experience but varies. I would just stick to noise level for now while you are testing. Even noise of 4 should be sufficient with denoising but again do some region render tests first.

[Beanzvision]

Hi there, I would also increase the pass amount. This article may also help you with that. Overall, I can see that you are making some good progress :)
https://support.chaos.com/hc/en-us/articles/4528236666257-How-many-passes-is-enough-in-Corona-for-3ds-Max-

[THAMIN]

Great help...
its good

[maru]

I think the main issue here is not allowing the image to render for enough time. Keep in mind that 3 passes will never be enough for reasonable quality. Usually you need about 100 passes, in some cases and especially in higher resolution less could be enough, but probably no less than 50. Additionally, in your scene there is strong, sharp sunlight bouncing around, which is hard to sample efficiently.

You could try various approaches depending on what is the priority for you:
- Rendering in lower resolution (this will give you higher image quality in less time)
- Increasing the GIvsAA value in Render Setup > Performance to 32 (this will improve the quality of light bouces per pass)
- Adjusting your materials (making them darker will let you reach higher quality faster)
- Adjusting your lighting (using an HDRI with softer sunlight, adding some interior lights, etc, to light up the darkest areas in the interior)