Re: [ccp4bb]: scaling high resolution to very low resolution data

[Dirk Kostrewa <dirk.kostrewa@psi.ch>]

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Dear Juergen,

assuming that both data sets were collected from the same crystal and the low 
resolution data set was measured after the high resolution data set, I would 
simply apply an overall scale factor without any B-factors, because a 
B-factor for the overlapping range 6-4.5 A wouldn't make much sense (in my 
opinion) and radiation damage usually results in a decay of S/N in the high 
resolution range. I would also recommend to do scaling and merging on 
intensities and calculate Fs from the merged data set.

Anyway, good luck!

Dirk.

On Friday 28 March 2003 15:48, Juergen J. Mueller wrote:
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>
> Dear all,
> I would like to merge a high resolution dataset (15-2.05 A) and a very
> low
> dataset (110-6 A). Both have been evaluated with different programs
> and now we have mtz-files with f's.Wilson scaling will fail, because the
> low resolution data are beyond 4.5A. FHSCALE results in scaled data
> within the overlapping region only. SCALA ended up (after generation of
> multi-record MTZ files from normal mtz-files) with strange results (may
> be due to wrong parameter settings: Scaling protocol constant,B-factor
> isotropic).What is the recommended method?
> Pierre Dubois had the same problem in 2000 but I did not
> find any answer in the ccp4bb-FAQ's.
> Thanks,
> Juergen

-- 

****************************************
Dirk Kostrewa
Paul Scherrer Institut
Life Sciences, OSRA/007
CH-5232 Villigen PSI, Switzerland
E-mail: dirk.kostrewa@psi.ch
Phone: +41-56-310-4722
Fax: +41-56-310-4556
WWW: http://www.sb.psi.ch
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