Dear Chimera Users

I want to measure the distance between an atom (or group of atoms) and the protein surface. I need a sort of residue depth, so the shortest distance between an atom and the molecular surface would be fine for me. I found that command "measure distance" could help, but it does not appear to be working, because every atom that I choose give aproximately the same value. For example (I have only one molecule loaded in Chimera) :.

measure distance #0:1@ca #0

log info:

minimum distance from #0:1.B@CA to 1752 atoms, 1 surfaces = 1.4814

measure distance #0:58@ca #0

minimum distance from #0:58.B@CA to 1752 atoms, 1 surfaces = 1.4484

The second selected atom is clearly deeper inside the protein

Thank you in advance

Sergio