Help with Vray Materials or i could go MAD

[fadi3d]

Hello guys i hope someone could help me with this

when making walls material of a white matt finish do u usually use reflection ? if so what IOR ( i googled with no sucsess for this particular material ) and how much reflection.

does this material come with noise (i included an attachment)

thank u in advance

[TheMulf]

No, I never put any reflection on standard wall paint. What are your GI settings?

[BrianKitts]

Yes, all things are reflective, you need a reflection on walls if you want a realistic rendering.

 

I don't think paint finishes are standardized enough that IOR's could exist for all paint manufacturers.

 

I always put a falloff map in the reflection channel (set the type to fresnel), set to black and 25% grey and then set the glossy value real low (.5 or .6) The other thing you can do is to put a small bump map in the diffuse channel at a real low value to simulate the nap of a roller that applied the paint. It will give you a realistic look when the walls are in the foreground and will slightly breakup the reflection.

Edited September 2, 2008 by BrianKitts

[Ky Lane]

Yes, all things are reflective, you need a reflection on walls if you want a realistic rendering.

 

I don't think paint finishes are standardized enough that IOR's could exist for all paint manufacturers.

 

I always put a falloff map in the reflection channel (set the type to fresnel), set to black and 25% grey and then set the glossy value real low (.5 or .6) The other thing you can do is to put a small bump map in the diffuse channel at a real low value to simulate the nap of a roller that applied the paint. It will give you a realistic look when the walls are in the foreground and will slightly breakup the reflection.

 

Exactly what I used to do with Vray

 

However, I dont think your problem is material settings - looks lighting/settings related to me.

 

4:46am rendering... dedicated

 

How long did that render take?

[BrianKitts]

However, I dont think your problem is material settings - looks lighting/settings related to me.

 

oops... got caught up in the question and didn't look at the image that close....

 

Ky's is right your irradiance map settings are too low, the large splotchy noise you are getting is most likely from a lack of hemispherical subdivs.

[Ky Lane]

oops... got caught up in the question and didn't look at the image that close....

 

Ky's is right your irradiance map settings are too low, the large splotchy noise you are getting is most likely from a lack of hemispherical subdivs.

 

[fadi3d]

hello guys,

thank u all for ur answers and sorry it took a while for me to reply (i'm not getting email notification from CGa for some reason )

first of all i know that the right way is to use reflection. just how much is the issue ?

it also might be a Gi issue but i've attached a render where the gi is quite high and i still have the same problem. irr high 50 -30 and lc 1200

AA is also high (i think AA is good )1-30 clr 0.003

what i've noticed is if i put an sphere vray light affecting the ceiling only the problem is solved (wich i consider as cheating )

please note that my goal is to light a scene with only Vray sun and sky and the real existing lights (i mean where i have a spot i put an Ies etc...)

are any of u able to do this or am i doing anything wrong ?

do materials not hit by direct light show noise in render even with high Gi settings ?

please help if u can

thank u

Ps ky u do celebrate wildly

[TheMulf]

That kind of noise still looks like GI noise, you may have to go higher because of how little light is in the room.

[Nic H]

are you using vray light mat in those soffits? (everyone of your images seems to have this detail) dont use vray light material to light stuff, it needs really high GI to work properly. vray lights instead.

 

try changing your min / max in IMAP to -6,-1. That should clear up those blotches.

 

if you use lwf you should be able to light a room pretty easily with sun/sky/physcam and a few ies/spots/vray lights.

 

as for reflection use what looks right?

[fadi3d]

Mulf i know it is Gi Prob

Nic u are right, 2nd pic uses Vray lightmat but the 1rst is strictly Vray lights.

i do use LWF and save as Oexr and adjust exp with Vraycam or in post (thank u for that advise it saves a few more tests and is more flexible )

as for the Imap Settings i will test those and see

i am sorry to use a pic that is not mine (Pls see attachment )but just to show u what i mean.

there r few lights in this scene and yet it is all bright something i can't acheve yet (note that i use LWF)

any input is appreciated

thank u

Edited September 3, 2008 by fadi3d
missing attachment

[WeazzeL]

sorry for digging this old thread, but did you solved your problem? or at least the basic way to achieve this last render? or some tutorials ..

[fadi3d]

i treat each scene differently, but every answer was helpfull so follow the suggestions.