Typical White Shader for Ceilings and Walls 4 LWF

[grantwarwick]

It has a massive difference.

The way you explain will blend between the two materials evenly across the whole material whereas my method only blends the material based on the angle (Which has to manually be tweaked based on what you observe in nature)

Now a real question is, should the top coat still have fresnel enabled (Set to a high value of 12-18 ) and still be blended with a falloff map. I'm not sure what is physically correct, I usually eyeball it.
Maybe I'm breaking reality by not enabling fresnel on the top coat. ALWAYS USE FRESNEL &#^#$&@

Left is my method.

[Macker]

I suppose the best way to approach it is to get down to thinking about what happens to light as it hits the (real world) material. Does it have a top coat? If so, what is it?

If we're still talking about standard, plain white wall paint, then I'd go as far as to say that it is far, far more simple than all of this. If however you are talking about say... wood with a varnished surface, then you're definitely along the right path I think.

[trixian]

T.b.h, your example looks wonky. The Blended version suffers from saturation burn and basically just looks like it has a higher IOR than the regular one.
Also, you are approaching some type of metallic effect here, and I was under the impression that we were talking wall paint just recently. That I why I can't see the use for a layered shader for simple wall paint.
Do you Aussies paint your walls with acrylic and then coat them with a clear shellac after?

[grantwarwick]

basically just looks like it has a higher IOR than the regular one.

The ILM lighting artists I've spoken to have said they used this exact method due to the control it gives you and I agree with them, I've had more trouble blending mats through eachother than over eachother.

Edit: I've spent some time today testing different methods. I still think its best not to use fresnel on the top coat and blend with a fresnel map.
It just doesn't look right the other way imo.
You don't get predictable results at all and its impossible to get top coats sitting "over" the surface.

[GLASS-CANVAS]

Base coat 256 subdivs
Topcoat 128

Very high sampling but with correct aa threshold renders VERY FAST.

This render took 10 mins, absolutely noise free

That's very interesting, Grant, thanks for that. I don't suppose you could be persuaded to screenshot your VRay render dialog settings and post them here? I think I've tried 20 different combinations of DMC settings but I'm still not happy.

[ARTECONI-CGI]

Hi All,

I agree Bill, very interesting topic. I'm reading the thread about the sampling right now.

Peter, I'd like to ask you about your workflow if you don't mind.

Are you saying that beside setting the output to 2.2 you are still correcting all your inputs (colors and textures) manually with a color correct .4545.
Could you elaborate the reasons about it?

I think this is correct but again a big headache when you work on big scale project and with few other people (that are generally used to the LWF from the MAX panel)

Am I wrong or I have seen you using the LWF button in a couple of occasions? One of your tutorial on your blog and a couple of Christmas ago at 3D London @ Hayes Davidson?
I'd like to hear your opinion about it...


Morne, I'll be interested in reading this article from Lele about setting the output at .25. Are you able to provide a link to the thread?

Regards,

Giacomo.

[glorybound]

Morne, I'll be interested in reading this article from Lele about setting the output at .25. Are you able to provide a link to the thread?

Regards,

Giacomo.

I remember this, and it was a pain. I had my whole library "corrected" that way. It took my forever to reverse that one it was do longer the fad.

[ARTECONI-CGI]

Hi Bobby,

I have just found it.
So you're saying that this method is obsolete with the latest versions of vray?

Regards,

Giacomo.

[peterguthrie]

Hi All,

I agree Bill, very interesting topic. I'm reading the thread about the sampling right now.

Peter, I'd like to ask you about your workflow if you don't mind.

Are you saying that beside setting the output to 2.2 you are still correcting all your inputs (colors and textures) manually with a color correct .4545.
Could you elaborate the reasons about it?

I think this is correct but again a big headache when you work on big scale project and with few other people (that are generally used to the LWF from the MAX panel)

Am I wrong or I have seen you using the LWF button in a couple of occasions? One of your tutorial on your blog and a couple of Christmas ago at 3D London @ Hayes Davidson?
I'd like to hear your opinion about it...


Morne, I'll be interested in reading this article from Lele about setting the output at .25. Are you able to provide a link to the thread?

Regards,

Giacomo.

might have used the lwf button but that was probably just a quick way of translating an old scene that wasnt set up correctly.

these days I have max gamma ON and use it to correct bitmaps, and then I use vraycolor to adjust all basic colors after hearing Vlado say in Venice that vraycolor was a bit faster than the max color correction map.

[ARTECONI-CGI]

Hi Peter,

Thx for your insight.
Do you use the vraycolor on all the maps or just the diffuse? I mean what about the procedurals and gradients? I guess you go back to the color correct...

Regards,

Giacomo.

[ARTECONI-CGI]

i forgot, you can obviously plug the vraycolor in the procedural maps...

[peterguthrie]

not sure yet, only just adopted this approach!

[simon123]

I may have read this thread wrong. But i'm using a HDRI for external scenes and some of the materials obviously are being tinted by the sky HDRI.
Can i use the correction methods discussed to achieve a sphere of pure white set to 230,230,230 by colour correction or adjust the camera custom balance to compensate for the difference.
?

thanks!

[glorybound]

VRayOverrideMtl

http://help.chaosgroup.com/vray/help...verridemtl.htm

[Morne]

I may have read this thread wrong. But i'm using a HDRI for external scenes and some of the materials obviously are being tinted by the sky HDRI.
Can i use the correction methods discussed to achieve a sphere of pure white set to 230,230,230 by colour correction or adjust the camera custom balance to compensate for the difference.
?

thanks!

Add a sphere in the middle of your scene and give it a white material, 230 is a bit high so try maybe 210,210,210 or even lower (no colour correction). Set your camera white balance to neutral. Expose the cam so you can get float values below 1 on the sphere
Now measure the brightest spot on the sphere and check the rgb for that. Now punch that measured rgb into your camera's white balance.

You will notice the default white balance for the vray cam is a light blue (D65). That is just to give you a head start for you scene lighting. If you add a vray sun it will add the vraysky (without clouds etc) Typical middle of day scene with this will give light blue sky. The sky will tint your entire scene blue. That's why they set the whitebalance in vraycam to blue. It removes the blue (from the sky) so your scene looks more natural.
So then armed with this info, if you have a HDRI sunset with heavy red/orange sunset, then you would make the whitebalance red/orange so that your whites is white.

You don't always want a 100% white balanced image however, depending on your needs. Sometimes a bit of a warm tint can make your images more inviting