White exterior paint

[glorybound]

I am having a heck of a time with white exterior paint. I can drive down the road, on a sunny day, and white paint is white and you see all the detail. In VRay, I have tried all the tricks and my white is blown out. If I go any lower in color things look gray. I have tried the color mapping tricks and the VRay frame buffer highlight burn. What's the trick? I am having some luck with a dirt map in the diffused, but not much.

[Morne]

What are you using currently?

For quick distance shots where you wont see the grain of the paint and texture, I stick to a:
difffuse of around 180
reflection around 50 to 128, depending on setup
gloss about 0.6 to 0.65 depending
(if its very far away and not the main focus of the shot, I'd even make reflection 0)

I use similar values for interiors actually, but add texture where you will be close enough to see grain, bump etc

[joconnell]

I reckon tone mapping would help with this a lot - most cameras compress the really hot values quite a bit and the new aces stuff does something similar too. I'd look at doing a final colour correction layer over your comp in photoshop so you can keep working linear as usual and then use a bit of a curve to pull those burnt out areas back into somewhere more pleasing.

[glorybound]

I am getting close. My client has a thumbnail and you can't really tell that it is white board-and-batten that small.

[dlparisi]

I'll often add a vraydirt map with a small radius to white siding to enhance the recesses a bit and give a little bit of contrast.

[rusteberg]

232 diffuse value on a lambert material is equivalent to a bright white sheet of copy paper in this world. Which is to say that’s about as white as white gets... from there it’s simply a matter of balancing the light affecting that surface.

You can can see all the detail on a White House driving in daylight because the aperture of your eye is never constant, always changing.

[glorybound]

Can you explain this "lambert material"? I see talk about lambert materials, but I don't know what it does.

[Karol.Osinski]

You can can see all the detail on a White House driving in daylight because the aperture of your eye is never constant, always changing.

I agree that our eyes has to do A LOT with it.
Apart of using lower white values..I find using high sun intensity together with HDRI tends to burn a lot, even if you turn off the HDRI and see that your sun is actually dim and yellow, those two multiply together in some weird way in my opinion.

Another trick coul be to render DIFFUSE with surface details and comp in post.

[joconnell]

Can you explain this "lambert material"? I see talk about lambert materials, but I don't know what it does.

It's just a material that only has diffuse - no spec and no reflection.

[rusteberg]

What joconnell said, Bobby: https://en.wikipedia.org/wiki/Lambertian_reflectance

[glorybound]

Okay, but I am not seeing anything for this in MAX. How do I do a Lambertian material?

[rusteberg]

oh my.....

[glorybound]

I am assuming there isn't anything special to do. Plain VRay material with no reflection or specular is a Lambertian material?

[joconnell]

Bingo. There's kinda nothing in the world that's perfectly lambert (maybe chalk or if you're going for flat cartoon stuff) so most 3d renderers don't do a standalone lambert material. As you say if you have all reflect / refract at 0, you're only using diffuse and pretty much lambert.

[glorybound]

My white's suck! This is white with no reflection or specular. One plane is gray and one plane white.