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I seem to get shading errors in Octane if I have smoothing on but I get faceting if I have it off.
Any suggestions concerning what I can do about that?
The shading errors are more pronounced if the model was exported to modo from another application than they are if the model originates in modo.
Freezing my geometry is a solution but at the expense of a much heavier model.

Sorry for the novice questions but I'm just starting to learn about rendering.

By the way - I LOVE the daylight in Octane.

Your mesh is to low poly. Insert a few edgeloops around the edges you have problems with and you should be fine.

Cheers.

Chris

or, as said before in other threads, you can "detach" the polygons according to the smoothing groups in 3ds max by hand, or using a little handy script found here: http://www.scriptspot.com/3ds-max/scrip ... hard-edges
Good luck!

you can just enable the use of smoothgroups in the obj import preferences in octane to have octane do this for you on import.

Radiance

I'm finding the same thing with objects generated in Modo (401) and saved or exported to OBJ. I have the import of smoothgroups turned on in the preferences. this image is just a simple cube and cylinder. enabling the smooth feature in material properties definitely helps smooth out facets but introduces these undesirable dark shaded areas.

rodney71 wrote:I'm finding the same thing with objects generated in Modo (401) and saved or exported to OBJ. I have the import of smoothgroups turned on in the preferences. this image is just a simple cube and cylinder. enabling the smooth feature in material properties definitely helps smooth out facets but introduces these undesirable dark shaded areas.

interesting error

I'm pretty sure that the smoothing toggle in Octane only smooths the normals, not the mesh, which gets rid of faceted edges. Octane, in this case, is trying to render a cube without edges and corners, which is why the cylinder is only shaded wrong at the top and bottom.
Somebody correct me if I'm wrong, or say it more clearly, I haven't been doing this too long.

I get it at the bottom of simple shapes and at the point where the back of a cylinder rounds away out of view.
It can almost make the object look semi transparent.
I think Greg is correct, maybe somebody can give us a more technical explanation of the difference between mesh smoothing and normals smoothing so we could understand it a bit better.

That's the downside so far.
The upside is that the light in Octane is beautiful.
I've been experimenting with very simple shapes in monochrome colors, and they look much more subtle and clear in Octane than in any of the other add on renderers that I've tried so far.

Here are two quick attempts that I made.

In Blender, I didn't do anything to the default cube, but I put it on it's own material so that I could control the "Smooth" parameter of the material independent of the cylinder. For the cylinder, I used smooth shading and then used an EdgeSplit modifier which breaks the cylinder surface into the two caps and the side (while still retaining a single object).
I downloaded Modo and had a try in it. I couldn't find anything similar to an Edgesplit modifier, but Imported the scene into blender and performed the Edgesplit modifier on the cylinder and imported into Octane. I unchecked the "Smooth" parameter on the cube and left it on for the cylinder.
I just need to figure out how to do the similar function as Blender's Edge Split in Modo. But, since Blender is free, you could always just add it to your pipeline.

Phil

PhilBo wrote: I just need to figure out how to do the similar function as Blender's Edge Split in Modo. But, since Blender is free, you could always just add it to your pipeline.

Phil

Modo does in fact have an edge split, its under the Edge tab > Split. IMO it might be useful to have a edge split option for OBJ import, it can split base of boundary of materials, Thea does this - great time saver.