smoothing continuity with narrow tris.

[pixelrush]

Hi ,
I have a wee normals issue that is ruining the appearance of some of my renders.
In the pics attach you see tris showing even after smoothing - unsmooth case shown for comparison.
This is particularly obvious in the middle band where the curvature is mostly in one direction.
The tris are not that good in a cg modelling sense - they are long and narrow but it is exported from a CAD program like that and I dont have control over it.
I would have thought though it would appear smoother than it does.
Is this primarily a fault of the mesh? I use Blender to prepare the scenes. Would it help to subdivide or such these faces?
Perhaps Octane should smooth this better or there could be a setting exposed to tweak the angle for normals smoothing?
thanks for ideas

[radiance]

try disabling the 'use vertex normals if supplied' in the OBJ import prefs panel prior to import, to let octane recalculate them, and see if that helps?

Radiance

[pixelrush]

Sorry to be slow getting back to this.
I tried your suggestion and its quite a bit better for some reason. Still a bit off here and there from what I would like but I'll use that until I figure out how to make the topo better. Thanks.
I tried selecting the ugly shaped faces and edge subdividing to make them less long and narrow but that didnt give the desired results - probably made it worse actually. Smooth vertices wasnt helpful either.
Perhaps it has deviations/waves away from a nice surface because of the CAD exporter accuracy. I'll try out some other settings etc in that and see if I can get an improvement.
I am not quite sure why the tris would show up like this though..I would have thought they would blend together but..
I asked Blender to select faces greater than 0.5 deg from a selected one and it doesnt find many either side so its fairly flat.
I'll keep experimenting

[radiance]

usually there are options in apps that export OBJ where you can define the quality of the vertex normals generated.
blender has this (high quality normals for rendering, which i recommend enabling)

Radiance