Same surface, but it looks like a patchwork of dieffrent surfaces.

Is it possible to do something about this?

Are these surfaces connected?
Try to use Join tool.
Also please try to do a final render.

Same after Join and also after render in Layout

NB: Delta surf, spec 16% and Roughness 25%

In v. 11.6 it looks like this...

off hand what is the smoothing angle set to?

Have tried 89 60 45

After several tests, I probably found a possible problem. It's not a bug, but it can affect LightWave rendering.

I'll fix it and if you have the chance to test the beta version of LWCAD 2018, let me know if it helped or not.

LWCAD 2018 beta phase will start in a week.

Viktor

Thanks Viktor.
I will look for the LWCAD 2018 beta