Noise free

[Tong]

trying to do noise free setup with DE, Light portals etc... with acceptable time, maybe someone can help :roll:


http://www.zshare.net/download/59384819edf77f28

http://ipicture.ru/uploads/090430/thumb/ei1oSHOR10.jpg (http://pic.ipicture.ru/uploads/090430/ei1oSHOR10.jpg)

[artdude12]

It seems that the Light Portal is extending the render time.
If replaced with a luminous rectangle, the render time is much faster.
Sorry, I'm not much help.

[BerTiN03]

And I suppose it's perfectly noiseless artdud12 ?

Can you show us a render please ?

[Tong]

It seems that the Light Portal is extending the render time.
If replaced with a luminous rectangle, the render time is much faster.
Sorry, I'm not much help.

Can you show a render please ?

[artdude12]

Oops my bad Tong.
I had your fast preview setting on during an editor render.
It turns out that if I use the Manul setting, then the render time
goes back up.

:oops:

[nycL45]

Tong, why DE (Detail Enhancement "on") for that scene?

Leonard

[Tong]

because it part of setup, that gives better shadows, setup not only for this scene, it`s mine default setup for interiors :oops:

but anyway if you turn it off, that does not change idea

with DE
http://ipicture.ru/uploads/090430/3I4e36R2s3.jpg

without DE
http://ipicture.ru/uploads/090430/6VYlIh32JW.jpg


with Light Portal
http://ipicture.ru/uploads/090430/FFDKSR9erk.jpg

without Light Portal
http://ipicture.ru/uploads/090430/puPHR43hh5.jpg


with Light Portal (8 samples, )
http://ipicture.ru/uploads/090430/s25MEIST1s.jpg

[Tong]

only sun
http://ipicture.ru/uploads/090501/1mUrDymRzn.jpg

portal
http://ipicture.ru/uploads/090501/AaiW1VUWul.jpg

portal with store to irr map
http://ipicture.ru/uploads/090501/x33UdRQW9O.jpg

scene with shadow objects
http://www.zshare.net/download/59426333cca4be37/

seems store options destroy portal like shadow object source and makes vray use it only for GI calculation in Irrmap

[BerTiN03]

WHy have you lost half off the GI shadows with storing with IR map, Tong ?

Storing with IR map only gets aways speculars, it normaly doesn't change the IR result, while it's quite reducing time, we're ok.

[Tong]

try by yourself

http://www.zshare.net/download/59426333cca4be37/

But the Vraylight has an option 'store with irradiance map'. This option actually means 'treat direct light as first bounce GI light'. Instead of casting direct light, the Vray light will now cast first bounce GI light and thus it will be calculated by the irradiance map. This also means that when it hits a surface, and bounces back, it will become secondary GI light, and it will be calculated by the secondary GI engine, QMC GI in this case.

So by setting the Vraylight to 'store with IR map', the result will be that there is no direct light anymore, only GI light. This means that all shadows will also be created by the GI light. The consequence of this is, that shadow quality doesn't depend on the Vraylight subdivs anymore, but the it is controlled by the GI settings, namely the irradiance map (and QMC GI for secondary bounces). This is important, the Vraylight subdivs do absolutely nothing if 'store with IR map' is checked!

(note that this option only works if IR map is set as first bounce GI engine. If you have for example QMC GI for first and second bounce, and lights with the 'store with IR map' turned on, these lights will not cast any light!)

This step is very very important, you should really understand the difference between 'store with IR map' turned off or on, and the difference between direct/first bounce and secondary bounces.

The disadvantage of this option is that there will be more first bounce GI light, but worse, also more secondary bounced GI light (calculating detailed GI light, especially second bounce, is very processor intensive). This means you have to rely on IR map and QMC GI calculations for the creation of nice shadows. In product renders this is not such a big problem, because there will not be much secondary bounces anyway. Light that hits the top of the spheres for example (=first bounce), will bounce back (second bounce) right into the sky. So this second bounce will have no effect on the rendering. Only a bit will bounce in between floor and objects, or from one object to the other. But the secondary bounces will not have such a big influence on lighting and shadow creation.

This will become more of a problem in interior scene lighting. There, the second bounce will not go to the sky, but it will probably hit a ceiling or wall, bouncing again and again... So in these scenes, the secondary bounces do have a great impact on final lighting look and shadows. So in this case, it would be a good idea to reduce the amount of GI light, by replacing the first bounce by direct light ('store with IR map' turned off). Think about it, instead of relying on first bounce GI light to start with, you now start with direct light which will illuminate a lot of the scene already (quality is perfect, it is direct light), then there is first bounce (ir map) and then second bounce. I will show this in the interior lighting tutorial.

To summarize, for product renders you can greatly benefit from the store with IR map option, as there are not much secondary light bounces. You will need to improve the IR map settings, resulting in longer GI calculation, but the actual rendering of the image will be a lot faster, as there are no difficult area shadows to render anymore. The total rendertime (GI calculation + raytracing the image) will be a lot lower than when you use true raytraced area shadows (here GI calculation will go faster, but actual raytracing will take a lot longer, so combined total result is much longer).

http://www.aversis.be/tutorials/vray/vray_studio_lighting_02.htm

[Tong]

sun only, default settings (adaptive 0.85, noise trh 0.01, A DMC 0.01 1/4, cache and irrmap the same for all tests) - 2 m 12 s
http://ipicture.ru/uploads/090501/z7tncsmjBc.jpg

added portal with 8 samples, we have noises - 7 m 56 s
http://s2.ipicture.ru/uploads/090501/nVUihMyRdc.jpg

16 samples 9 m 7 s
http://s2.ipicture.ru/uploads/090501/NWR4qJMFtc.jpg

36 samles - best image
http://s2.ipicture.ru/uploads/090501/7u9Q13EDTR.jpg

store to irrmap, shadows goes away - 2 m 52s
http://s2.ipicture.ru/uploads/090501/J06Gba0Sg1.jpg

8 samples, noise trh 0,005 no difference with 0,01 - 8m 23s
http://s2.ipicture.ru/uploads/090501/e6k0R6qBOt.jpg

16 samples, noise 0.005, 9 m 40 s
http://s2.ipicture.ru/uploads/090501/4HDBDe1Wx4.jpg

adaptive 1, no difference 7 m 34 s
http://s2.ipicture.ru/uploads/090501/60wvxCgW4V.jpg

8 samples noise trh 0,01, AA Min/Max 1/100, added LC prefilter 100, filter Nearst 10
we have near 16 samples and 0.01 noise - 15 m 18 s
http://s2.ipicture.ru/uploads/090501/bRgBk22FmP.jpg

the same with only AA DMC min/max 1/100 without LC changes
http://s2.ipicture.ru/uploads/090501/vxzD3cMrfR.jpg

Noise trsh - no diff

Adaptive amount - no diff

AA - yes different, but render time increase to much

Light subdivision - gives difference

[Tong]

Noise Trsh 0.01 AA 1/100 8 samples 15 m 18 s
http://s2.ipicture.ru/uploads/090501/vxzD3cMrfR.jpg

Noise Trsh 0.005 AA 1/100 8 samples, Quality lower then 36 subdivs in portal and time 30 m (3 times more)
http://ipicture.ru/uploads/090502/vLRsUuI44G.jpg


conclusion: better change light portal subdivs with 0.01 noise and default 1/4 A DMC, then anything else