Psy - my scene for you to look at...

[Frances]

Hi Psy,

Here is that scene file:

http://www.surrealstructures.com/VRay_loft.zip

This will be removed from my server on 8/21/04. It's ~ 2.8mb and I'm not sure how well my server will handle the bandwidth. So get it while you can.

Here are a couple of sample images:

My lame settings:


Using Saluto's settings:


[edited to add]
I should mention that there are 5 photometric linear lights. In my real scene I'm using the manufacturer's IES file, but did not include it in this scene.

[Dynedain]

woah! deffinatley think it is your glass giving you problems...either turn on fresnel reflections or drop a gradient in the reflection map slot (or use EGZ glass )

[paulison]

Hi Frances,

I am very new to Vray but have had the most success from studying this tutorial:

http://www.osmosis.com.au/info/tutorials.htm

Try saving the settings from the interior tutorial and applying them to your model. This has worked for me so far. I have learnt a great deal from this tute but im not sure how it will help you. They have helped me but I think i'm not very advanced yet. I find the settings in this tute strange but seem to generate quick images for me that still look fine (at higher resolutions anyway)

I dont know whats going on in the first image? What kind of settings were you using? (so i know to stay clear)

your second image looks great to me using saluto's settings...how do higher res images come out? Id try render at the resolution he specified which was 1920x something as my guess is it needs higher IR sampling at your resolution.

Im very interested in hearing some decent solutions from people.

One thing that bugs me about the IR map undersampling is a lack of shadows in corners etc. Maybee im just imagining this...

[Psy]

Alright, I'll see what I can do to help you get a better result and time for your scenes.

I've gotten the file and if you so desire I can host the file on my server. Bandwidth ceiling is quite high so I doubt it will overload on my end.


Psy|

[Psy]

Some questions straight off the bat, what modelling package do you use to make your rooms in?

[Frances]

Some questions straight off the bat, what modelling package do you use to make your rooms in?

Thanks Psy,

I don't really see a need to host the file elsewhere.

As for modeling, I use Rhinoceros.

[Fermi]

Hi Fran,

First, please pester me as often as you want, only problem is may be you'll reach my limitations too soon. I did pester specially Gonçalo, but also Marc and Leon when started using VRay... well, they insisted I should use it, so...

Select all your glass objects and exclude them from GI genreate and recive, in VRay, System Object settings.

What some people did was calculate and save imaps with glass window objects hiden and then reuse GI from precalculated file, and turn glass on at render time for reflection/refraction....

We can say it won't contribute to the illumination,

For illumination test renders:

-Inmediatly low GI Irradance map Min/Max rates to -5,-4 (for instance)
-HSph subdivs, from 100 to 50 this will cut Imap calcualtion time about the half (I'd have said start with something as low as 20, that will have impact on Imap quality, but much much greater on render times, so until you have Illumination roughly set, keep it low, you'll be able to crank it up later)

Photometric lights in your scene... what's the purpose? to reproduce accurate actual projected fixtures behaviour? is that really necessary?, if it is then I probbly won't be of much help, but if it is not, if you only need to produce the "feel", first whing we do is delete them.

A similar level of general illumination can be achieved without the lights, increasing GI and Environment multipliers.

Try this: delete all your Photometrics (or turn them off) , set First diffuse bounce multiplier to 3,0 Secondary Bounces to 1,0 (it's max value in 1.09) GI Environment muyltiplier to 7,0.

Well, now the scene is not what you want yet, but if you turn antialiasing adaptative to -2, 1 it renders in some 51 seconds (800x600) dual xeon 2,8 downgraded to 2K SP4 because of XP problems, this mean NO HT enabled.

From here we coult try to reintroduce the artificila lights if they are needed, my apporach would be fake them of course, not using actual photometric lights (unless that was actually the reason of the visualization)

Geometry with selfilluminated material and VRayMtlWrapper has worked great for me, standard lights with limited ranges (a la fakiosity) have also worked great in some other situations.... as we add further lighting, we can then turn the blowed up multipliers for environement down, and adjust First diffuse bounce....

Later, we might consider lgith portals or simply area lights for the window openings (so we fake the glass we removed from GI partial light scatering)

I know, still a long way to go, and I am not best consultant for interior images + I am a faker, but I think really fast test render times are a must, specially when we have lot of testing ahead.

hope it helsp somewhat, later more.

I'll emailyou the scene I've downgraded as described above, just open it, and hit render, and see if it helps or not.

Cheers

Fermí

[Fermi]

Oh, I see you already have one Skylight portal.... hmm, perhaps one actual light per opening would work better... must go home now, tomorrow I'll try to give it a second go.

so long

Fermí

[Psy]

Another contribution to all that is, try to use vrayshadows whenever you can. Adv. Raytraced shadows for the most part do not speed up or otherwise overly help your rendertimes.

Secondly, try to use vray materials as often as you can. Almost all of your materials are normal max standard materials w/ vraymaps applied in the reflection channels. Vray renders faster when it's dealing with it's own maps not max's. Any time where you can use a vray material, use it instead of maxs.

I disagree w/ Fermi over the IES lights strictly because sometimes the client requires that you use them. I'm assuming that you Frances are using them because the client wanted them, but just like Fermi, I hid the lights so that they wouldn't participate in the lighting solution.

My result is rendering right now, but will take some time due to the insanely slow work computer that I use. (Getting fast results with Vray on a P3 700mhz w/ 128mb of RAM running WinXP Pro is a big deal for me)



Psy|

[Frances]

Hi Psy,

Um. Well. I had the scene all set up with VRay mats and using VRay shadows. With that scene I produced the renders, so the rendertimes reflect any benefit I would have gotten from those two things. But then I didn't save it. I didn't have time to change it all back or to double-check anything. Of course the material settings have lots to do with render time, so there is also that angle of approach.

Hi Fermi,

The photometrics are there because the client is a lighting manufacturer and they have supplied luminaire models and IES files. I have to use them - and they would notice if I didn't, since they are their babies.

[paulison]

Fermi I found your post very helpfull for my work anyway, thanks.

[Fermi]

Hi Fran,

May be I am wrong, but if the very lights are the reason for the visualization, in this scene, perhaps radiosity is the tool to go in your case:

You have a job to do, the sooner the better (multiple deadlines involved :P )
You are a proficient discreet's radiosity user, a rendering engine which one of it's goals to be IES standard compliant, you have some IES compliant lights as main reason of the visualization job, a clean model, radiosity friendly, if only because that's how you are used to do it through years, it is small space, so you'll be able to mesh it to a fairly size + radiosity processing won't care about number of lights...

Afterwards, with enough time ahead, try to repro or even improve the radiosity work using VRay, but not with tight deadlines pressing hard...

Hey! VRay is the rendering engine I am daily using in my work for the last 2 years, I am not against it, on the contrary!

my 2 cents of Euro


Hi Paulison,

You are most welcome, I am happy you find it useful, but don't thank me, I don't deserve it, picked everything form this forum and the people in it.

Cheers

Fermí

[Fermi]

Ok, turned lights on again

There is a hole in the structure object that allow lot of light in, fixed it.
Render times sitll kept low enough to allow lot of testing lights and materials:

With Very low settings:



Just with Low set:



No Daylight Ultra low settings:



No Daylight more reasonably low settings:



Well, while not able to make a great image now, at least have some fast enough render times that may eventually allow testing to improve it! :P

hope it helps

Fermí

[Fermi]

One last test trying to recover a bit of the lost contrast... yet the photometric lights having a presence.

Have removed (turned Off) the skylight portals here, and readjusted light & enviromnment multipliers

With Very low settings:



And with similar settings but cranking quality a bit up... obviously, render times go up again more than we'd like, to consider them testing times





Placing the light fixtures in would help understanding where the light actually comes from.
Ok, that's all for now

Cheers

Fermí

[paulison]

this illustrates very well the effect of the HSubs setting. nice render times. Id be interested to see a higher resolution image with higher AA and IR map settings

also, do the photon map setting effect the quality much ?(for second bounce)