Interior / Exterior window setup

[Builtdown]

Hi,

It would be great to collect here some ideas and tips to make a great window glass for interior and exterior shots.
I haven´t been succesful yet to make one that I would be satisfied.

I have tried specular material, glossy material with low opacity, and the mix of the both. I probably have wrong attributes.
How would you setup the material (reflection, fallof, incidence angle, etc)?


Here is my latest test. This has windows with just glossy material with about 15% opacity. I would like to have stronger reflections and more visible background. But if I raise the reflection, the background gets lighter. If I lower opacity, the reflections vanish... :

[Builtdown]

No-one has been able to make good window glass with Octane?

[whersmy]

No worries, there are different arch. glass options I believe. Search the forum for "glass falloff" / "fake glass" or "architecture glass" !
http://render.otoy.com/forum/search.php

Nice render btw, can you enlighten us a bit more about the setup? Is the exterior an hdri + sun?
Kernel seems like DL?

I think you got the gamma settings + mood just right, which can be tricky

[BorisGoreta]

I just put default specular material and that's it, to speed things up I also check the fake shadows option. Why complicate things ?

[Builtdown]

Hi,

Thanks, but no luck yet.

First to Whersmys question : The setup was 1 Octane light as a sun + Octane lights for each window. No hdri. Kernel is PathTracing.

I tried default specular material for the window glass but the Octane lights became visible behind specular glass so the windows were totally white (no background visible). Why is this?

I have attached the files of a simplified version of the scene. Would someone like to test the scene and try to make a good looking glass windows with it? With the current glass in the scene the reflections are too low and the background behind the windows is too light.
Thanks in advance!

[juanjgon]

The problem in your scene are the lights that you have in each window. The reflections of this lights are visible in the windows, and this reflection makes the windows white.

A "unseen by reflections" feature could fix your problem, but we don't have this feature in Octane yet.

Can you please try to set the Shape Opacity to only 10% (or even 0%) in the lights? ... Perhaps this could make the lights invisible to reflections and cast light anyway. You can add more power to the lights if the scene becomes too dark after this change.

-Juanjo

[Builtdown]

Hi, thanks.

This is a problem because area light in windows is a fundamental workflow in professional interior shots.
I hope you come up with a solution for this in the future.

In the meantime, maybe you can help with these couple of node-questions:

1# If I use Glossy material as the window glass (low opacity, high specularity), is there a node that could ramp up the reflection over the full white (255,255,255)? Like in LW you could use ie. 200% reflection value.

2# I can´t get a grasp of the Fallof texture node. I would like to set some fallof to the Glossy material (window glass), so that the opacity would be lower at the 90 degree angle and higher at lower angles. And visa versa, specularity lower at 90 degree angle and higher at lower angles. How should I set up the nodes?

[BorisGoreta]

#2 you can do that with refraction index in glossy material

what do you gain by putting lights in windows, it just makes the renderer slower because it has to sample those lights, what is wrong with leaving just daylight environment ?

[Builtdown]

>#2 you can do that with refraction index in glossy material

...for opacity also?

[BorisGoreta]

I think you are complicating things too much, as I said before, normal window glass is default specular material plus you can check fake shadows for faster rendering ( this disables caustic calculations ). \

So for glass you don't need glossy material fallof refraction index voodoo.

Maybe if you just remove those window lights specular material would look just fine ?