LOD Node build lower cell size of the grid.
Input / VDB Grid:
Input vdb data for LOD. You must connect this input for create.
Output / VDB Grid:
output LOD result vdb data.
LOD Level:
Defines level of the grid. Level 0 means same level with original Grid. Increase 1 level makes half resolution each.
Affect All Channel:
When checked, all channel (velocity, color, UVW) get LOD result. Some time LOD result get strange artifact, especially on the channel. In that case, you may try to use uncheck this.