Hi Dan: for the "to-do" list: the grid command should support output to
the .cpp4 map format, which is almost universally used in crystallography
and cryo-EM work. This would save the users many headaches in file
conversion.
Sander and rism both have code to read/write this format. There are probably
toolkits otherplaces (e.g. cctbx).
From DAC: