About noise in general

[Morbid Angel]

so technically speaking, with subpixel on, does the entire image render faster, or just the areas that have the glossy highlight?

[cecofuli]

Usually, I see the buckets stop on the area there are glossy shader. But usually, we have all shaders with glossy =)
And, I don't want to talk when the bucket are on very bright area. VRay goes crazy!
Do you remember?

DISCUSSION


EDIT: noise threshold not 0.001, but 0.01

[Morbid Angel]

yes i remember that one, I couldn't get anything out of it But to me this particular image does not make any sense to be slower. In the chair area especially, if I render exterior render of a metal object, it renders in seconds/minutes. Why interior reflection has to take that long?..

[cecofuli]

I don't know. Now, in all my indoor scene, I use BF+LC + subpixel ON by deafult + "Bernard" method.
Fast rendering, good quality and the noise is low. Only I get up a bit the specular value.
I don't have time to fight with subpixel and its "problems".
I left Universal Setting for interior.
But, also, in the outdoor rendering, with subpixel ON or OFF (retrace ON in both) I have a huge difference in rendering time (x2.5)
With only one, white shader. I have better illumination in the dark area, but the difference in rendering time is too much.

[Morbid Angel]

weird! something does not add up to me. If this is a grey material, shouldn't subpixel affect just the speculars?

[cecofuli]

I don't know. If you want I will send you the simplified scene.
I open now the old files and render again. The difference is correct.
On my website the final shot with sub-pixel mapping ON

[Morbid Angel]

sure post it, I'm sure vlado would want to look at it too. Is it using multiscatter?

[cecofuli]

Yes. Multiscatter. But the file is very simple and easy You can see the "difference" in any outdoor scene.

[Morbid Angel]

by the way, I was just looking at your other scene again, one with the chairs. Its is odd to me that you use universal settings in it, with 1/100, but your materials and your lights do not adhere to the universal setting principals, for example shaders have 32 subdivs in them, lights ies ones have 256. This will kill the render time, when using universal.

[cecofuli]

From in the Universal setting Spot3D help:

(*) Leave all subdivs anywhere at their default values. They won't have any effect anyways - the 100 AA subdivs will almost certainly override everything else.

So, 8,32, 256 is the same.

[vlado]

From in the Universal setting Spot3D help:

(*) Leave all subdivs anywhere at their default values. They won't have any effect anyways - the 100 AA subdivs will almost certainly override everything else.

So, 8,32, 256 is the same.

No, 256 is not the same

Best regards,
Vlado

[cecofuli]

Ah, ok... but usually I don't use 256 subdivs. I think was our setting error. They are 8 by deafult in all my scene.
But, good to know

[jasonhuang1115]

cecofuli, are you sure the animated GIF is not showing the difference in the opposite way? I thought with Sub-pixel on, it will render faster and darker.....I am speaking for Maya. Maybe in Max the UI is designed the other way around?

I am curious how does Arnold handling the noise issue? I tapped into it shortly months ago and it appears to me the quality control is as simple as one quality slider plus you can tell it how many reflect/refract bounces you want. Don't remember if Arnold has a sub-pixel mapping option though. Not trying to derail the focus of this thread, but just wondering...

[Morbid Angel]

yes I think its best to leave all the subdivs as default, they may or may not contribute to longer render time.

[vlado]

Well I got the scene from Dmitry, but it has some quite weird settings in it...

Best regards,
Vlado