[WIP] - Cottage House

[zchen]

Hi,
This is some preview images of a project I'm working on.
Two sets to deliver; exterior and interior.

It seems that my scene is really struggling with noise. There is alot of it, especially in the interiors.
Could you please help and give pointers on how to get cleaner results?

SCENE SETUP (for interiors):
- PG's HDRI for lighting
- Corona Portals on major openings
- Double-glazed windows for double-reflections

- Rendered images are @2000px
- PT+PT / MSI @50
- 200 passes (roughly 7-8 hrs per image)
- GIvsAA @32
- LSM @2

PC SPECS:
 - i7 5820K @ 4.0Ghz
- 32gb ram
- GTX550

Of course, general comments  are welcomed!
Thanks a lot





















 

[FrostKiwi]

Well, 7-8 hours with that much noise is bs ;]
Use UHD cache, it will help incredibly cleaning up interior with HDRI. Portals are optional, dont obsess over them.
MSI@50 is too high. At that point you might aswell turn on unbiased mode.

Try to 15 or even 10 instead. You have no caustics and brightness loss will be onl measureable, not visible.
It will help alot, if you have a bright patch of hdri, bashing little reflective rays into the far sides of the interiour, that may not cleanup even after hours.

You seem to have a strong shadow, if it's from the HDRI, then portals wont help at all, as its not very good with sharp very bright spots on the hdri dome.

[zchen]

Thanks Saires for the tips, that's a good bunch of useful knowledge.

Well, 7-8 hours with that much noise is bs ;]

I'm telling the truth I swear :P

Use UHD cache, it will help incredibly cleaning up interior with HDRI. Portals are optional, dont obsess over them.
MSI@50 is too high. At that point you might aswell turn on unbiased mode.

Try to 15 or even 10 instead. You have no caustics and brightness loss will be onl measureable, not visible.
It will help alot, if you have a bright patch of hdri, bashing little reflective rays into the far sides of the interiour, that may not cleanup even after hours.

So are you saying that turning up the MSI is only necessary when dealing with caustics or to brighten up reflective surfaces?
Also for the exterior shots, I should leave PT+PT right, for the large number of foliage?

You seem to have a strong shadow, if it's from the HDRI, then portals wont help at all, as its not very good with sharp very bright spots on the hdri dome.

Yes, the shadows (interior) are from the HDRI as it is the only light source in the scene.
I have no technical understanding of the render engine (I should probly read more about it), so I'm presuming that coronaPortals are only helpful to reduce noise in cases where the coronaSun is used?

I might just get rid of the portals altogether.

[zchen]

One more thing,

There are some slight (red/green-ish) color bleed on the wall/ceiling in the interior shots, that are due to the dark flooring and exterior grass.

Is there a way to eliminate (or at least reduce) that bleed effect?
I tried turning down the wall's reflectivity, but doesn't seem to do anything.

In Vray, there's an "GI-contribution" value that I could lower on the grass object for example to make the colorbleed less present.

[FrostKiwi]

Lowering MSI will kill off fireflies, which ones averaged against a long render time produce noise.
Especially with strong HDRi and/or glossy reflexions can save a bunch of render time, while not making any real difference.
Yes, it will reduce the brightness of caustics but otherwise it doesn't affect the scene usually.

You can use The rayswitcher material to disable that colorbleed. No problem.
Tutorial for this exact case has been created

[zchen]

Corrected the settings and will render another test tonight to see if the noise situation will improve.

While you're talking about MSI,
if I may, I'll point to this beautiful renders by Michal Timko in the gallery section.
https://forum.corona-renderer.com/index.php/topic,5719.0.html
He mentions using MSI-100 in these images. Do you see a specific reason why his MSI is so high? Would he be fine with just MSI-20 or 25?

[FrostKiwi]

Corrected the settings and will render another test tonight to see if the noise situation will improve.

While you're talking about MSI,
if I may, I'll point to this beautiful renders by Michal Timko in the gallery section.
https://forum.corona-renderer.com/index.php/topic,5719.0.html
He mentions using MSI-100 in these images. Do you see a specific reason why his MSI is so high? Would he be fine with just MSI-20 or 25?

If you care about bias, or have strong caustics, then yeah, you may leave it high. At 100 though, you can just aswell go 0 for unbiased. But this is not a magic setting, that will change your image for the better. If you have the rendering power, you can go unbiased, but I urge you to try it out yourself to find any difference.
(Except super long rendering times.