The problem of Octane and Rhino IOR 1

[Micha]

Hi Paul,

at Rhino per default is used IOR 1 for diffuse materials without reflection. So it follows the concept "Since we live on Earth, all IOR values assume that 1.0 is the value for traditional linear light behavior. And thus, air has an IOR of 1.0."
http://www.cineversity.com/wiki/Index_o ... ion_-_IOR/

If I render a rhino scene not special adjusted for Octane, many materials are wrong shown with high reflection at Octane. Could you please add an option that allow to get no reflection per IOR 1? Maybe per internal material parameter conversation or per general Octane IOR 1 fix.

An other problem is that Reflectivity is 0 is shown as full reflectivity. In this case no reflection should be shown or?

Fixing this two issues would help to jump from Rhino rendering to Octane.

Ciao,
Micha

[face_off]

Micha - it is unclear if you are referring to the "Index of refraction" of specular or glossy materials - which are you referring to pls? For your reference, the formula for the Octane "Index of refraction" for glossy materials is (Reflectivity % / 100 * 7) + 1, so if Reflectivity is 0, the index will be 1.

An other problem is that Reflectivity is 0 is shown as full reflectivity. In this case no reflection should be shown or?

Again - not sure what you are referring to here....

In investigating these issues, I found a bug where updating the Rhino material was not correctly updating the Octane version of that material. This is fixed in the next release. In the meantime, you need to click Refresh to migrate changes to Rhino materials to the Octane scene.

Paul

[Micha]

Here an example, the rail with Reflectivity o% should be looking like 2% and not like 95%.

Reflectivity=0%

Reflectivity=2%

Reflectivity=95%

[Micha]

I did some more tests and it looks like the Rhino material connection is complete buggy. Here some examples:

[formatio]

I think Micha refers to rhino materials and their appearance and behavior during render in octane.
Micha have you seen this:

[Micha]

And so you get control over roughness, IOR, reflectivity so that a material looks like a rough plastic? I tried it but it doesn't help. Also I can't disable the "reflectivity 0 will cause full glossy" behavior that cause the wrong look of materials with reflectivity 0.

[formatio]

But why would you want to use rhino mats in octane render?

[face_off]

Micha - the conversion of Rhino materials to Octane materials is very basic, and because Octane is a physically based renderer, some of the settings in the Rhino material do not translate directly to Octane materials. So you are really going to want to convert you Rhino materials to Octane materials in order to get the realism and quality you are after.

Paul

[Micha]

Yes, I understand, but the connection of the basic Rhino material functions should work. Is it to much to expect that:
- roughness and reflection intensity should are working
- IOR 0 means no reflection and not metal reflection

Please try to fix the missing links.

[Micha]

But why would you want to use rhino mats in octane render?

Because often I have a lot of simple objects in the scene. For example a complex architecture scene - peoples (simple diffuse material), bikes/cars (plastic, metal), billboards, plants ... . Often this object are quick imported from the hard disk and the Rhino materials are ready. And for example if I render per Vray no additional tweaks are needed. It should not be a problem to support the basic Rhino functions.