Hi all I was trying to analyze the hydrophobic surface of two very large structures ( 3 chainsx 900 aa each so 2.700aa). As expected the default surface calculation has failed. Normally for electrostatic potential what works for me is making a mol map (molmap #3 4 gridSpacing 0.5) and then calling the pdb2pqr and apbs servers directly from chimera, which is very convenient. However I cannot find an analogous way to make it with hydrophobicity... Since the surface fails for such big molecules, the straight forward way (present-3interactive surface hydrophobicity) does fail as well... Then... is there any server than can be called from chimera, to get hydrophobicity as an attribute to be depicted? Or alternatively could you suggest any server that gives output hydrophobic column, compatible to get it after to chimera attributes? Reading a bit I found that, not as electric fields, that can be computed for structures, hydrophobicity comes just for the sequence, without taking into account the neighbours and context... P.D: I have managed to represent in other programs the hydrophobic surface, but I really want to make it in chimera, to make it more consistent and easy to organize myself... Thanks a lot! and sorry if the question goes beyond Chimera... Marta