Scan to Parts
Scan to Parts selects a region of a scan. You select on the point cloud preview, which keeps the viewport responsive on large scans, and the selection carries over to the full mesh. It's on the Natsura toolbar under Scans, and it's the Trim Geometry step of the Import Highpoly wizard.
Use it to cut away the parts of a scan you don't want, or to isolate the section of trunk you want a tiling bark texture from (see Scan Rig and Scan to Tube).
Inputs and outputs
Wire the scan's Proxy (from Import Highpoly) into the first input, and take the selected part from the first output, Proxy. The other inputs and outputs aren't needed.
Selection
Select Parts holds the selection. Delete Non Selected (on by default) keeps what you selected and deletes the rest; turn it off to delete the selection instead. Selection Resolution, under Advanced, is the voxel size the selection works at.
visualize, under Display Settings, switches the viewport between the point cloud proxy and the full mesh.
Status
Scan to Parts is experimental.
Scan Rig
Scan Rig gives a scanned section a skeleton by placing points down the centre of the tube, so Scan to Tube can rebuild it as a clean tube.
Scan to Patch
Scan to Patch cuts a square patch out of a scanned tube, for a tiling texture of one bark feature or one that sits more easily beside other materials.