Typical White Shader for Ceilings and Walls 4 LWF

[Morne]

Hi all

I'm in search of the optimal shader settings for your typical white wall/ceiling boards/bulkheads that looks good, doesn't burn and renders this century.

This is my current settings that gives me good results, but I think it could do with some updating:
Diffuse: 220,220,220
Reflect: Full White (255,255,255)
Fresnel: Ticked
Refl Gloss: 0.65
Subdivs: 128



I'm thinking that perhaps I can change the reflection from full white, to maybe mid grey (128,128,128 )

Anybody know what Bertrand or Peter's settings are or maybe care to share your take on this?

[peterguthrie]

pretty much the same I think Morne, will check on the reflection amount I use though..

[Slazzo]

One question, when you guys use almost white diffuse + reflection for walls, I know that VRay does use energy conservation law, but when having the reflection does the GI bounce less from surface? and we need to turn on Reflect GI Caustics to compensate the light amount bounced from surface?

[3LP]

Hey,

Just my 2 cents :
I tend to use my white at 240 (220 seems a bit low for white no?)
Highlight at 0.65 but I set my reflect glossy at 0.85 ( I like to see the reflection a bit sharper and it renders a bit quicker)
Subdiv 64-256 depending on the subdiv of the rest of the scene (dmc/light/global/etc) the samplerate pass is your friend!
I like to set the roughness at 0.5 when it's been hit by straight sunlight to avoid having too much of overbright areas.
I still struggle to use this one with the right approche, if you guys have thoughts?
I would love to know Peter's ans Bertrand's settings like you said though.

Stan

[DanielBrew]

This was discussed before in this thread:
http://forums.chaosgroup.com/showthr...ht=white+paint
At the time my white paint was using rgb 200,200,200 I've since changed to rgb 180,180,180. Although I sometimes cheat and use higher values for ceilings.

[peterguthrie]

I've always avoided LWF/gamma discussions as I have a pretty out of date technique which was born out of a distrust of how MAX handles that sort of stuff, but if you are using some kind of gamma corrected workflow, do you also colour correct your plain colour values or are you just guessing values?

My white value is 230 but then that goes in a color correction map with gamma set at set at 0.4545

reflection amount was just 75 and glossiness 0.6

Interesting that you tried roughness too Stan, I'm pretty sure I tried once too but really could never see any noticeable difference

[DanielBrew]

I've always avoided LWF/gamma discussions as I have a pretty out of date technique which was born out of a distrust of how MAX handles that sort of stuff, but if you are using some kind of gamma corrected workflow, do you also colour correct your plain colour values or are you just guessing values?

Hey there's nothing wrong with distrusting how Max handles anything!

I do gamma correct rbg values using the VRayColor map, for example if I'm given a pantone reference as an rgb. I also scale them down so that none of the rbg components are above 180. I do the same to bitmaps by setting the 'RGB Level' in the output section to between 0.7 and 0.8. This makes sense to me as nothing should be brighter than my white paint.

As I said, these values have crept down over the years and once I got used to working with darker materials I actually found scene lighting easier. Because there is less contrast between light materials and darker ones I can use stronger lights without the lighter materials blowing out. There is also plenty of headroom increasing the brightness of individual materials to create a particular look. I guess it all boils down to personal preference.

[peterguthrie]

my thinking is that if say a particular wallpaper is being used with an exact shade of green then if I need to have a plain wall with that same green then I need to gamma 2.2 it as well.. I did try turning on the MAX gamma settings at the start of my last project, but once I found that I'd still need to inverse gamma all my colours anyway I gave up the idea of changing my workflow

[3LP]

Yeah, I never really saw any difference with roughness apart from materials where the sun is hitting straight on it and it would be completely over-bright, it seems that the roughness is actually pulling everything back a little bit like if it was doing a local "HSV exposential" :-p
I can't really explain it better, it's still one of those dark areas in VRay for me, I wish I could understand it correctly, if you guys have any tips, let me know

To know that your guys are putting sometime 180 as a white point, and tone down everthing, make me think it's quite a battle to have correct color codes from client. I guess we allways have to play with it cause of the reflection and shadows. Clients doesn't allways understand that it actually affect the diffuse color
Stan

[grantwarwick]

Technically your paints should be made up of two layers. A blurry Base coat of glossiness .5-7 and a top coat with no fresnel, but blended over the top with a fresnel map.
This should be a low value 1.2, 1.3 and it should be highly glossy.

Go analyze a white painted wall...
Front on you see no reflection but side on it almost becomes a mirror.

[3LP]

And that's exactly the kind of answers that I love
(A *.mat file is always appreciated )

Thanks mate,

Stan

[Macker]

Front on you see no reflection but side on it almost becomes a mirror.

I'm sat in an office of white walls, and none of them become even close to a mirror at glancing angles.

[tricky]

I agree, our white walls are nothing close to a mirror. Even difficult to appreciate any sort of reflection. Are your walls painted with gloss paint? (mmm...nice!)

[pixela]

my thinking is that if say a particular wallpaper is being used with an exact shade of green then if I need to have a plain wall with that same green then I need to gamma 2.2 it as well.. I did try turning on the MAX gamma settings at the start of my last project, but once I found that I'd still need to inverse gamma all my colours anyway I gave up the idea of changing my workflow

I do the same. But don't always depend on Colorcorrect map or anything but trust my eye more.

[pixela]

I think there are big difference in white walls too.
For example in the area I live, most of the building are white washed and this is much diferent than standard exterior white paint.
White-washed walls have a very reflective nature and almost translucent that increase the brightness with kind of an SSS effect. (This is not an scientific explanation at all, I don't know about the chemistry but just my impressions).
On the other hand, the aqua based white paints have rather different nature and they absorb some of the light and are less brighter than white-washed walls.
For interiors, I think gypsum-based white pilaster + paint is much diferent than the plastic paint as well.