[richardfollett]

Been away for a while and I have having fun with grass .
Why is it looking like this? This is applied to a simple plane which is 2 x 1 metre. I downloaded the materials from maxwell material database

What am I doing wrong?

[JDHill]

I'd recommend having a look at the displacement section in the Maxwell Render manual (pages 71-73) before anything else. Basically, in Rhino, you are going to want to use a Mesh, rather than a Surface, so that you have easier control over the density of the mesh plane -- this, in addition to the displacement's Precision and Smoothing parameters will control how tightly Maxwell displaces the pixels in your displacement map.

[richardfollett]

Thanks JD, I will take a look.

[kami]

what you'll need in this case is to subdivide your plane (/its mesh).
You can do this by activating "custom mesh" in the properties panel and adjusting the settings until the mesh is much finer (eg. 20 to 30 subdivisions per length)