Rendering-Times Interior

[PdZ]

Dear Chaosgroup,

I really dont know what Iam doing wrong. What I could improve or what is to be expected since iam using V-Ray 5 in conjunction with Interior-Renderings.
I get extreme long renderingtimes and they are also noisy. I didnt change much in the rendersettings.

I have a VERY SIMPLE Office Scene with just 6 Chairs, 1 Table, 1 carpet which has displacement and not much more.
Using V-Ray Sun and Skydome. 2000px width -> 16:9 format. No other light.
Materials are simple. Just 2 textures -> leather for the Chairs and carpettexture. Everything else are metal-, plastic- or glassshader. Nothing special here.

Lightcache -> 900 Subdivs. AA -> 1:16.

I takes AGES to render this simple scene. With 3.7 IR/LC I would have been finished by writing this forumpost. I know that Lightcache looks a lot more realistic than the approximization of IR/LC but that cant be the future...
So I must have 3 Threadripper 64 cores to render the same time to get an very similar result?

What is happening here? Could you pls explain/help me pls?

Thx in advance,
PdZ

[shaio]

Hey PdZ ,
If possible, can you please share the scene with me, so I can take a look? It sounds like a very simple setup as you describe it, but often times if we recreate something on our end, it isn't reproducible right away. I also suspect that it might have something to do with the displacement, so it will be best for me to examine the scene, so I can try and help you.

[PdZ]

dear shaio ,
Thx very much. I send you the scene. Forgot to mention that also the leather chairs have displacement.
But I cant imagine this could be the reason. I will also try to render the scene while turning off all displacement.

[PdZ]

Seems not to change anything. Even then it says: 2h 34m 37.9s est....
For a 2000 px image... on a 24 Thread CPU. I dont know... something is off here

[PdZ]

Not to mention: The renderings not even noisefree and applying denoiser resulting in artifacts. Iam full of despair right now...

[sirio76]

Hi, maybe there's something you can improve in your setup, 2.5h on a 24core machine for a 2K image seems a lot (although I can not be 100% sure without knowing your scene complexity).
For reference I've just posted this scene: https://forums.chaosgroup.com/forum/...-modern-living for a 4K render (so 4x the size of your render) and on a non overclocked 8core CPU it took about 6h with a noise threshold of 0.007, there are both displacement and hair.
On a 24core AMD TR machine probably will be rendered in less than 2h in 4K and about 30" in 2K.
Be sure your CPU is running at full speed using dedicated benchmark (under stress to be sure is not throttling), beside that without looking in to your scene is difficult to know what's going on.
Another advice, build in denoiser is not that good and that force you to use lower threshold (= longer render time), but with the latest update I'm experimenting with the Intel denoiser and from my early tests using that could cut render time by a large margin, unfortunately is not ideal for animations but for stills it should get the job done much better than standard V5 denoiser.

[RwVision]

Hi Guys,

Sorry to brag once more, but Vray5 times, noise... are just laughable.
sirio76 , your scene is marvelous of course - yet it has a lot of clean spaces, and the rendering still has noise! The wall shadows, behind curtains, the most simple reflection on the table and shelves on the right. The floor reflection of the seat is not even readable. Even after 2h on a very good TR?! This should render in 45mins tops.

3.7 with IRLC would have done it twice faster and cleaner. With detail enhancement you wouldn't even notice a difference in shadows, it would look even better with less noise.
I will say it again - Vray5 is a regression when it comes to rendering times, noise and denoising. Very sad.

[sirio76]

The point is always the same for me, that's a very little noise amount in my opinion and in that image I'vent used denoiser at all, the problem with V5 is that without a good denoiser even cleaning little noise is challenging. From my tests I see no significant differences in speed between 3.7 and 5 (of course comparing BR/LC on both) it's just that denoiser on old version was a lot better and while I was used to work with 0.02 threshold now I must use about 0.005 that is 4x slower, from that perspective I agree that there is a speed issue. The new Intel denoiser introduced with 5.1 seems better than the standard denoiser and now you can cut render time easily, but I still prefer good old 3.7 denoiser for sure.
About getting back to IM/LC, personally no thanks, that's legacy stuff IMO and even on 3.7 I've never used that since setup time required for IM and GI quality often offset any speed gain compared to BF (at least for my scenes), not to mention eventual GI issues, detail enhancement do not solves everything and thrust me when I say that I know really really well how to setup IM since classic scenes with tons of moldings and little detail requires a lot of attention to the GI settings
Maybe you perceive V5 to be slower because you were used to IM on the 3.7, I can confirm that IM was easily faster than BF on 3.7, it produces less noise too of course, but when you couple a BF solution with a good denoiser ther's no match everything considered, after all that's why almost the entire CG industry use unbiased solution these days.
I'm not saying that I'm happy with how things are now and I'm 100% with you when you say that denoiser was a regression (a huge regression!) , but the problem is not in the renderer speed itself, that's just a side effect as far as I can tell just check the latest images posted here: https://forums.chaosgroup.com/forum/...-store-concept the image done in 2" with Intel denoiser has more details/less noise than the image rendered in 20" using the standard denoiser, that needs to be addressed ASAP.
All that being said, I work in CG since more than two decades, I've never encountered a client that asked me for a cleaner image, they always asked a good image!

[sirio76]

Just to be sure nothing has changed from the last time I performed speed tests (it was during the V5 alpha version) I check again with latest build, every image rendered for 5" (400% zoom).
As I was expecting both 3.7 and 5.1 in BF (default settings) reach similar noise threshold, about 0.009, the noise is a bit more visible in 3.7 though.
IM with defaults settings was quite a bit quicker but resulted in visible splotches, so for a fair speed/quality comparison I slightly increase the IM quality by rising to 0 the max rate and by activating detail enhancement, that fixed the issue in this case but rised the noise level significantly, it was still faster than BR tough, reach 0.006 threshold and on flat areas (the one not affected by detail enhancement) it was less noisy.
The last test is made using 3.7 BF coupled with denoiser, no need to fiddle with render settings, no noise, no splotches, nice detail (but unfortunately you won’t get that on texture using V5 denoiser).
This is the complete scene done in V5 by the way: https://forums.chaosgroup.com/forum/...istrot-concept

[RwVision]

Hey Sirio - Many thanks for spending time on testing.

I must use about 0.005 that is 4x slower, from that perspective I agree that there is a speed issue.

Well, there you have it - even comparing BR vs BR - we are slower - And that proves that BRLC method wasn't improved in at least last 3 years!
There should be speed improvements every year.
I also would not want to go back to IRLC - but why the main method is still so slow and uneven in noise?

I've never encountered a client that asked me for a cleaner image, they always asked a good image!

Of course depends on type of work, you're always doing - my experience was that many times client asked for super clean renderings.

Quick sum-up from my personal experience - I do a lot of aircraft cabin animations - 4 years back I could render a crystal clear frame in let's say 10min. Now I would have to switch to 30min per frame with blurred denoiser and grainy corners from BR. It's a big no-go and still working on some projects in 3.7 unfortunately.


Must check the new Intel denoiser!

[sirio76]

As far as I know even on other platform Vray has not gained pure speed comparing to Next or 3.7, besides improvements in specific areas like dome light etc. For me that’s fine since even 3.7 was extremely fast, now all I want is a good denoiser to go back to that level.
The important things is to send the correct message to developers, if you report a speed issue with the BF engine they will look in the wrong place, wasting time on something that can not/should not be fixed, as said that’s a side effect of the bad denoising output.
Intel denoiser is ok, not as good as 3.7 denoiser but surely better than 5, I’m not totally sure but I suspect that during denoising it uses the diffuse filter to retain texture details and normal channel for the bump detail, it doesn’t use other components so if you have a flat diffuse color, no bump and a map in the glossiness slot, it will blur the details a bit, again I maybe wrong about this. Another limitation is that it won’t work for animation like the standalone denoiser.
When clients need super clean image and you lack a bit of render power, then I suggest using the Chaos Cloud, it will cost only a few bucks (really an irrelevant sum of money in my experience) but it will guarantee clean images in short time

[RwVision]

Lowering thresholds and other settings does not give noise free image, so even using any renderfarm is just over-rendering and not satisfying. That's clearly a BR noise issue, not just the denoiser.

If you have only one final image per project - I do really envy you your clients

Ending the off-top, cheers!

[PdZ]

I tested it again. Have a very simple scene. AA 1:24, still noisy. 4000 px. using my local PC with 12x 3.79 Ghz at 24 Threads and via Distributed Rendering another machine which has: 32 Cores at 3 Ghz with 64 Threads.
STILL having a est. Rendertime of: 5h!!!!!!!!

5 h? With that Power? I noticed when rendering with my slow a** graphicscard Nvidia Geforce 1070 TI its significantly faster than those machines. I know gracas are faster than cpus but 1. I dont believe that much and 2. with 3.7 I would have rendered the image in maybe 10 Minutes or less with those CPUs with DR and IR/LC.
And the rendering looks very weird when rendering with graphicscard. Cant show you an image though. But Something is wrong here. How is this possible?
What machines to you have guys? I want IR/LC back!

What is happening here?

[PdZ]

Also now adding another DR PC with 32 Core /64 Threads at 3.69 Ghz per Core. It estimates 2 h of rendertime.... that is slow as hell.

[seandunderdale]

Im not sure exactly what the issue could be but those shouldnt be your render times and I wouldnt blame Vray specifically. Right now for example Im rendering a heavy CAD asset of a Lexus interior, with full displaced seat and steering wheel perforations, a mix of VR scans and custom shaders, depth of field, Vray light materials, area lights, HDRI, and it renders a 2000 x 1125 in 15mins. Its camera animation and its noise free when played back. I am rendering on a 3990x cpu, but it sounds like you have enough render power to be getting fast renders also.