Re: [ccp4bb]: Filtering outliers in Patterson maps

[Manfred Buehner <buehner@biozentrum.uni-wuerzburg.de>]

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On Fri, 6 Jul 2001, Francisco J. Enguita wrote:

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> Dear Xtallographers :
> 
> Regarding the comments of E. Dodson yesterday about anomalous difference
> Patterson maps, I have a question, perhaps too much basic.
> 
> Is there any general rule to eliminate outliers when we are calculating
> difference (anomalous or isomorphous) Patterson maps for heavy atom
> localization ?. 

don't know about outliers. However:

If you want a clean map make sure that ALWAYS the input terms
were subjected to a proper ORIGIN REMOVAL operation.
(Then it's not a theoretically proper Patterson any more,
 but still a centric vector map, free of the origin peak's
 ripples, and that's exactly what you want.)


Good success !
                 Manfred
----------------------------------------------------------
 Dr. Manfred Buehner             Phone:  +49-931-888-4100
 Physiologische Chemie           FAX:    +49-931-888-4150
 Theodor-Boveri-Institut fuer Biowissenschaften
 Biozentrum der Universitaet Wuerzburg
 Am Hubland,  D-97074 WUERZBURG,  Germany
 Email:  buehner@biozentrum.uni-wuerzburg.de
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