Re: [ccp4bb]: What is the CCP4 (refmac5) equivalent of an omit map?

["Eleanor J. Dodson" <ccp4@ysbl.york.ac.uk>]

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Bart Hazes wrote:
> 
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> On Fri, 25 Jan 2002, Bernhard Rupp wrote:
> 
> > In pdb are a number of structures, where refmac TLS was used, (converted
> > to Uij s) and these structures show *extraordinarily* low freeR and R for
> > the resolution. So I wonder to what degree your higher rfactors of the CNS
> > model reflect just that, and also, to what degree those low TLS rfactors
> > reflect a truely better model?
> 
> If you talk about coordinates then the TLS model doesn't need to be better
> than without TLS, even if the R-factors are significantly lower. However, if
> you consider B-factors as part of the model, and of course they are although
> our normal display programs don't visualize them, then it appears that the TLS
> models are better indeed, especially at medium and low resolution. The lower
> R-free also suggests better Fcalc and thus a better map and possibly less
> model bias. All of these could help to actually get better model coordinates
> as well.
> 
> Bart
> 


 Thank you Bart! It isnt quite seemly to take part in this debate, but I
think the introduction of the handling of anisotropic temperature
corrections, and the snip-off from that of being able to recognise, and
correct for, TLS,  was a real step forward for refinement. And
refinement is the tool for getting  better model coordinates.
   All credit to Garib and Martyn ..
 Eleanor