Explorations in the post below seem to determine that Va sections create enormous project extents. This appears to require Rhino’s Ambient Occlusion renderer to spread its shading resolution across such great distances that a regular ridge pattern is rendered in closeup on surfaces which are in fact smooth.
Hi @djhg, after reading the linked post, it looks like the problem is related to invisible geometry located in far away high distance, that made the camera took a very high value. VA sections are unlimited in verticall directions. But this should not affect the camera Z location value, if there are no objects in faraway distances. I’ve opened your template posted in the other thread, replaced the Top viewport Detail (that has a big Z location Camera value), with a new Top view Detail, and the Z camera location value gets a consistent value.