Re: [ccp4bb]: refine occupancies with Refmac

["Hazes B." <bart@mrc-lmb.cam.ac.uk>]

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> No - it isnt, but the B values of the 2 conformations give you a very
> good indication..
> Do people think it is likely that the data can support such refinement
> unless you have very high resolution? 

> Eleanor

Individual occupancy refinement for all atoms indeed does not make sense
as a value of 1.00 is a very good estimate for the fulk of our models. 
However, you normally only want to refine occupancies for small groups of
atoms for which you have reason to believe that they have non-zero
occupancies. That is for sidechains build in multiple conformations and
bound ligands. There remains the problem that B-value and occupancy are
highly correlated in refinement, but if B-values increase to unreasonable
values it may be better to fix the B-value to a reasonable value and
refine the occupancy. 

Bart