Hi,
See the attached scene file. I am using a iso offset sop set to SDF . This is used in vops with a volume gradient to create a psudo N value.

This of course works on a sphere, but when I try to use volume from attribute sop to create a SDF volume I dont get any gradient values for the volume. Where am I going wrong in my approach ? .

2) I have been wondering if its possible to do all of this in VDB but have noticed that I cannot fill a volume when using VDB from particles. Interested to know if its possible

I have solved using a work around and the rasterize points sop, which uses an attribute to build a SDF. Still interested in why my initial approach did not work.

Rob