[ccp4bb] I/sigma in XDS output

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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

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Subject: Re: Protein expression in Minimal media (M9)
From: Cynthia Kinsland clk10 {- at -} CORNELL {- dot -} EDU
Date: 2007-04-19

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Subject: MSc in Structural Biology and Biophysics at Manchester, UK
From: Martyn Winn m {- dot -} d {- dot -} winn {- at -} DL {- dot -} AC {- dot -} UK
Date: 2007-04-19

Subject: I/sigma in XDS output
From: Michele Lunelli efunit {- at -} YAHOO {- dot -} IT
Date: 2007-04-19

Dear all,
I'm a bit confused from the output of the CORRECT step in XDS. In one of the
first tables I can read the mean I/sigma for each resolution shell, but these
values are much different from the I/sigma reported in the table at the end of
the output files, titled "completeness and quality of data set" for the full
data range with signal/noise > -3.0. For example, from the first table I have
I/sigma = 2 at 3.6 A, while from the second table I have I/sigma = 2 at 2.8 A!
What is exactly the difference between the two values? And which one is reliable
to decide the resolution cutoff?

Thank you in advance,

Michele Lunelli
MPI for Infection Biology
Berlin - Germany

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CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Re: Protein expression in Minimal media (M9)
From: Cynthia Kinsland clk10 {- at -} CORNELL {- dot -} EDU
Date: 2007-04-19

Next message:
Subject: MSc in Structural Biology and Biophysics at Manchester, UK
From: Martyn Winn m {- dot -} d {- dot -} winn {- at -} DL {- dot -} AC {- dot -} UK
Date: 2007-04-19