static Noise !?

[Komposer]

Hi,

please take a look onto the short mov file.
http://vimeo.com/38054939 (it will work in 50min)

You see a small region from a rendered sequenz.
Its not the first time for me, that I see this not so nice looking static noise.
The image is scaled up twice, for a better focus to my prob.

The quality is high enough for me, lower settings make the effect more intense.
Higher settings result to less noise, but basicly its the same effect.

It looks like the noise is static to the scene?!?
And when the camera make horizontal motion, the static noise effect is realy strange.

Perhaps I am completely on a wrong way, but for me it looks ugly.
Where is my mistake?
What can I do?

Thanks for hints...

[joconnell]

without being totally sure it might be the "time independent" check box in the dmc sampler here:



If you leave that on, the noise sticks to the screen, if you turn it off, you get dancing grain.

[Komposer]

Time Depentent is off / unchecket!
I think thats correct and mean "independent !?

[vlado]

It needs to be On, so that the noise changes from frame to frame (i.e. to make the noise dependent on the time). This option is the reverse of what it is in 3ds Max.

Best regards,
Vlado

[Komposer]

Thanks together..
Ok, I´ll try that tomorrow at first.
I think that it is!
But please tell me Vlado.
In which case I´ve to switch it off?
I think it must be on permanently!?

Best regards,
Jörg

[vlado]

In which case I´ve to switch it off?

Originally the idea was to turn it off when using irradiance map/light cache since in that case the changing noise could lead to flickering blotches. However, with the latest releases this is no longer necessary as V-Ray will turn the option off automatically just for the irradiance map/light cache calculations. The other idea was that some post filters for noise removal might work better if they can analyse the static noise.

I think it must be on permanently!?

You are right, it should probably be on by default - will make a note for it.

Best regards,
Vlado

[Komposer]

Vlado,
thanks for the middle in the night post!
Now I renders the scene with Time dependent checked!
And Yeehaa the static noise is gone.

But please take a look on this new Mov.
http://vimeo.com/38079600
Now there is a realy strange flickering in the blury reflections.
The rendered result from frame to frame is most realy different.

I´ve realy high settings in AA and reflection subdivs.
Adaptive amount is 0!

Any ideas what it could be?

K.R.
Jörg

[vlado]

It is due to not enough subdivs, but what kind of subdivs is hard to say. You could add a reflection, lighting and specular render elements to see which of them is noisy and needs more samples (if it is lighting or specular, then your light(s) need more subdivs, if it is reflection - then you'll need to increase the glossy reflection subdivs).

Best regards,
Vlado