Top Level Surface (TLS)

The Top Level Surface and used to model an uneven crest. TLS Markers are defined either directly at the surface (natural point) by manual placement or using targets with a known height offset by automatic placement. TLS Markers shall be established along the crest and describe the shape of the crest properly. For instance, they shall be placed at edges rather than at planar areas.

Adding Top Level Surface Markers:

1. Activate the checkbox Top Level Surface Marker in the marker list.
2. Set the marker the same way as done for the others. See Blast Site Markers | Standard Operating Procedures.
3. Optionally use the feature provided in the toolbar:
   1. Adds Top Level Surface Marker
   2. Remove the selected Top Level Surface Marker 
   3. Remove all Top Level Surface Marker