Verticality or Dip Dip SF - Highlight only the horizontal ledges of a cliff face

[jamble]

Hi Folks,

Totally new to CloudCompare and have watched a bunch of tutorials but none can assist with this issue.

I have a 3D mesh of a cliff face.
I want to select only the upward facing horizontal ledges to measure their areas.
I generate a Point Cloud from it.
I calculate Normals with perferred orientation +Z

I have tried:

Tools -> Compute Geometric features -> Verticality

Edit -> Normals -> Convert to -> Dip / Dip Direction SF

Both work to highlight the upward horizontal ledges (success!) BUT they also highlight the vertical faces and overhangs.
Any idea how to filter out the vertical faces and overhangs at all?

Thanks in advance :D

I've attached a couple of images so you can see what I am on about.
Image 1:Verticality
Image 2: Dip/Dip Direction SF.

[daniel]

If the normals are properly signed, you can try:
- additionally, extract the normal components as scalar fields, and find which SF (Nx, Ny or Nz - I would expect Nz) may differentiate the 2 sub-sets (based on the sign typically)
- or try your luck with the 'Stereogram' tool of the Facet plugin