[Chimera-users] Query regarding the Zone tool in UCSF chimera

Elaine, In UCSF Chimera, when I try to find all the atoms within 4A of a selected residue using the *Zone* tool, it selects several atoms around that residue. However, I am not able to understand which atom of the selected residue was taken as the reference point for calculating the distances. Please help. -- Prathvi Singh, Research Fellow, Department of Biological Sciences & Bioengineering, Indian Institute of Technology, Kanpur-208016