[Chimera-users] Coloring a surface according to distance from a selection

Hello, I can color a surface according to the distance from a single point or a plane, but is it possible to do it according to the distance from a selection (eg an other chain or molecule) ? My aim is to show the contacts between an antibody and an antigen. I tried the tool intersurf for doing it, but the result is pretty crude (low definition of the surface compared to the usual surfaces available). Thanks in advance, Paul