[phenixbb] Composite omit map

[Pavel Afonine]

Hi Sam,

> I have tried Polder Map as well as the conventional SA-OMIT map. My 
> feeling is that the conventional way gives better map for the ligand 
> at the 'good' region than Polder, but neither way improves density at 
> the 'poor' region.

I'd say it's more about getting convincing map rather than 
(artistically) looking better one. If three CC numbers that Polder map 
tool reports are in favor of the ligand then this is what you've got. By 
design, any sort of OMIT map is expected to appear worse than say usual 
2mFo-DFc map (it is naive to expect that by removing bits of model you 
get a better looking map).

Both methods you quote are to show you the map, not to improve the model 
so that in turn you get an improved map.

Pavel