frosted glass and render time

[oren]

hello all
please can you help me to find a trick that can tell vray speed with frosted glass in the scene

when i put this frosted glass in the scene the render time and the noise is going crazy... like 3 hours for HD and with aa 1 to 100 with noise threshold of 0.005... its not good

if i hide this frosted glass the render time go down to 1 hour with much more clear image

i tried to disable shadow of the frosted glass object and its not help

any help will be great !

the render:

[Morbid Angel]

I'm not sure that much can be done about this. 3 hours for HD render on one machine is not bad, if you are using brute force. 1/100 is a slower method too...Its a nice render btw.

[Neilg]

One way to speed it up is switch to IR / LC, pre calculate and save the light maps with the glossiness in the glass set to 1 so it's not frosted, then render from the saved light maps and turn the frosting back on.

[oren]

ok
update

i deleted the other side of the milk glass and put plane light as a real light outside the windows and i cut the render to 1 hour

i also put min 1 and max 24 and 0.005 on noise treshold and yes its go 1 hour for 2 k and look ok

the problem is... all the element \ passes look noise free and good butt only the reflection pass is grainy

im on the new vray with auto subdive ...im not going to go back to past and start adjust all suabdive ... but how i can tell the new vray to put more subdive to the reflaction area?

look at the passes

[flino2004]

try excluding the glass panels from GI calculation

[thanulee]

Try those settings:
- uncheck divide shading subdvs
- min shading rate =1
- Make all ur materials/light/gi 8 samples
- Adaptive amount set it to 1.0 (if ur using BF, if IM leave it default)
- use min max 1-5 and raise it up to 1-8 if u think is necessary (i think u dont need more for this image)
- use noise thresh 0.02 to 0.015 for starters and i think u ll get fine results. If u use denoiser even with 0.03 - 0.025 u can have a good image with much greater render times.

Cant explain all these in detail will take too long, is the way i sample just do a check and if u find this method working good for u (instead of the universal settings), i ll do my best to explain.
Happy new year!

[PIXELBOX_SRO]

hi Thanulee,
i ve tried your setup on a scene i have problems sampling usign universal method, but using your settings produces quite a lot of noise at above mentioned levels.
Unless youre using some magic button not mentioned

[thanulee]

Hmmm i use this method for everything without issues and without noise. Only thing that can cause u noise, is bf on this setup. If u can upload ur scene i ll give it a look, im curious if i forgot something.

[PIXELBOX_SRO]

i ve tried raising everything twice and it still does it...i ve got quite a lot of MB and DOF and glossies in the scene though so perhaps its not meant for such cases.
So my scene is still a noisy Loisy.
Cant post it unfortunatelly, got NDA on it, thanks for the offer though!

[zoranm]

Oren,

Try increasing default value of "Retrace" in LightCache to 8-10. It looks like vray is straggling to clear all the reflections behind glass.Reduce your image samples (bucket mode) 1/40, 0.005, it should be ok?

Good luck

Zoran

[thanulee]

i ve tried raising everything twice and it still does it...i ve got quite a lot of MB and DOF and glossies in the scene though so perhaps its not meant for such cases.
So my scene is still a noisy Loisy.
Cant post it unfortunatelly, got NDA on it, thanks for the offer though!

No worries. Well if u got dof from camera, values around 1-24 are needed. For any other case 1-6 is enough, if heavy glasses in the scene 1-16. This with IM shouldnt have any noise at all. With bf, is one way increasing bf samples as well.
Idk if i described u something wrong but i never had any kind of noise whatsoever with this method and i know with precision how to target my samples. I never go beyond 0.01. Too bad i cant have the scene i am so curious to see why the noise hehe.
If u want more on this sampling method, go check this one http://www.rese-arch.org/bundle/v-ray-essentials
Cheers!