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Re: [ccp4bb]: B-factor and resolution

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Peter Burkhard wrote:
> To me this sounds a little bit too simple. The resolution limit is
> not simply determined by the B-factor, as Ed suggests. Small crystals
> collected at on an inhouse source might diffract only to 3.0A while
> still being well ordered (i.e. low B-fators). From a large crystal
> using synchrotron radiation you may be able to reach 2.0A even though
> it has higher B-factors.
> Actually, this is really nothing new but it may (apart from the
> refinement-
> program artefacts) explain the low correlation between B-fators and
> resolution.

Agreed- the point where intensities fall below the noise level 
(resolution limit) depends not only on the rate of falloff with
resolution (B-factor) but also on how strong the intensity is to 
begin with at low resolution (affected by size of crystal) and the
signal/noise ratio (depends I suppose on beam intensity and 
collimation, what fraction of the beam hits the small crystal 
rather than going around it and contributing only to background).

So I wouldn't expect a correlation coefficient of 1.00. But 0.06?
No significant correlation between B-factor and resolution limit?