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riggles wrote:My MODO material is set to 2% reflection and 50% Fresnel

This should create a glossy node with an index of 1.3294. Specular should be set to 1.0, because the Index is controlling the fresnel curve.

funk wrote:"Specular materials" in octane are transparent/glass materials. Modo specular/fresnel settings have no effect on octane specular materials (only on octane glossy materials). You will need to set modo transparency to greater than 60% (you can specify the threshold in preferences > rendering > octane > Specular opacity threshold) before the plugin will convert your material to an octane specular node.

Sounds like you are getting confused by terms.

I know about the opacity threshold for creating specular materials, but I think I got confused with all of your and Paul's posts about specular/fresnel conversion formula, that I forgot you were only talking about glossy materials and not specular materials.

However, that does raise the question about how Octane handles the glass/specular material overrides when the material has lower reflection and high fresnel settings in MODO.

riggles wrote:However, that does raise the question about how Octane handles the glass/specular material overrides when the material has lower reflection and high fresnel settings in MODO.

Octane's specular material is physically correct so the "Index" (IOR) controls refraction and reflection (specular).

Modo has separate controls for reflection and IOR (called refractive index). This allows you to create materials that arent physically correct.

The only choice we have is to use the modo refractive index and ignore modo specular/fresnel/reflection etc

funk wrote:

riggles wrote:However, that does raise the question about how Octane handles the glass/specular material overrides when the material has lower reflection and high fresnel settings in MODO.

Octane's specular material is physically correct so the "Index" (IOR) controls refraction and reflection (specular).

Modo has separate controls for reflection and IOR (called refractive index). This allows you to create materials that arent physically correct.

The only choice we have is to use the modo refractive index and ignore modo specular/fresnel/reflection etc

So, I should just leave the specular value at 1.0 on the Octane material all the time? Maybe I just need a little more relearning when it comes the more physically accurate methods of Octane. Octane's "specular" value is MODO's "reflection" value, and I'm not used to having it set that high, for glass or glossy materials.

riggles wrote: So, I should just leave the specular value at 1.0 on the Octane material all the time? Maybe I just need a little more relearning when it comes the more physically accurate methods of Octane.

You are free to edit the octane material any way you want once it's created. Paul is just using some simplified rules for the initial conversion (eg. when you dont have an override, or when an override is first created from the modo material). Using Octane nodes will still keep the material psychically accurate automatically because they only allows you to control a limited set of attributes (as opposed to modo which has a large number to cover all bases)

riggles wrote: Octane's "specular" value is MODO's "reflection" value, and I'm not used to having it set that high, for glass or glossy materials.

It's better to think of it another way. Octanes glossy specular (1.0) is modo's reflection/specular color (1.0,1.0,1.0 - note: Paul has decided to only use greyscale values by converting the color to an intensity)

In octane, you need to get used to setting specular values using IOR (Index). We don't have this in modo, but many other renderers do (vray)

If you want to set modo's spec/reflection using IOR, I wrote a little script which helps:
http://community.thefoundry.co.uk/discu ... 559#776559

When creating physically accurate materials in modo, you will rarely see a spec/reflection value higher than 5% (except for metals which can be around 60%). If you listen to the latest modcast ( http://community.thefoundry.co.uk/discu ... 525&page=0 ), Allen actually mentions this too.

When rendering, the render info (samples calculated, elapsed time, etc) doesn't update if I'm not moving my cursor. If I move the cursor out of the viewport and stop moving it on the screen, the info stats will pause until I move the cursor back into the setup viewport.

When rendering, the render info (samples calculated, elapsed time, etc) doesn't update if I'm not moving my cursor. If I move the cursor out of the viewport and stop moving it on the screen, the info stats will pause until I move the cursor back into the setup viewport.

I have noticed this too. I'm not sure the exact cause, but I will investigate in more detail when building the next OSX release.

Paul

I've also noticed this behavior when adding images from the clip browser versus overriding materials that already have image maps.

For instance, when a MODO material with a diffuse map gets converted, both a filename, projection and RGB image node are created and plugged into the diffuse channel: However, when adding an image with the clip browser in the setup view, only the filename node is added: Shouldn't there be at least a projection node and perhaps an RGB/Greyscale image node added as well? Just the filename node isn't enough to really do anything with.

Shouldn't there be at least a projection node and perhaps an RGB/Greyscale image node added as well? Just the filename node isn't enough to really do anything with.

The plugin does not know if you intend plugging the image into an Alpha, Greyscale or RGB Image, so it simply provides the Filename channel and you do the rest. http://render.otoy.com/manuals/Modo/?page_id=169. Perhaps in the future a popup could be added when you drop the image onto the Schematic to allow you to select "Alpha, Greyscale, RGB or Node".

If there is no Projection node for an Image node - it uses UV mapping.

Paul

face_off wrote:The plugin does not know if you intend plugging the image into an Alpha, Greyscale or RGB Image, so it simply provides the Filename channel and you do the rest. http://render.otoy.com/manuals/Modo/?page_id=169. Perhaps in the future a popup could be added when you drop the image onto the Schematic to allow you to select "Alpha, Greyscale, RGB or Node".

If there is no Projection node for an Image node - it uses UV mapping.

Right. I was thinking that if Octane knew enough to create an image and projection node when a material with a texture map was converted, why couldn't it do the same when just a texture map was loaded. But I guess Octane doesn't know how you you want to use that image in that particular case. You could be wanted different projection modes for the same texture in different materials. And default is UV. Ok, got it.

face_off wrote:

When rendering, the render info (samples calculated, elapsed time, etc) doesn't update if I'm not moving my cursor. If I move the cursor out of the viewport and stop moving it on the screen, the info stats will pause until I move the cursor back into the setup viewport.

I have noticed this too. I'm not sure the exact cause, but I will investigate in more detail when building the next OSX release.

I was just trying a little animation sequence, and saw this issue is keeping Octane from moving on to the next frame as well. I have to keep moving the cursor around throughout the render to keep it advancing from frame to frame.

Also getting some "Command Disabled" notices when clicking the render animation button, but after I say OK to the notification, the render starts anyway but without the Octane animation dialog box that tells me what frame is rendering and that allows me to cancel it.