Re: [ccp4bb] To bathe or not to bathe.

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

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Subject: Re: To bathe or not to bathe.
From: "Nave, C (Colin)" colin {- dot -} nave {- at -} DIAMOND {- dot -} AC {- dot -} UK
Date: 2007-11-26

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Subject: Two postdoc positions in Structural Biology--University of Pittsburgh
From: Peijun Zhang pez7+ {- at -} PITT {- dot -} EDU
Date: 2007-11-26

Subject: Re: To bathe or not to bathe.
From: Richard Gillilan reg8 {- at -} CORNELL {- dot -} EDU
Date: 2007-11-26

Hi Juergen, the original calculation was done with I/SIG's from
scala. Yes, I am aware of the problems obtaining reliable and
meaningful I/SIG with CCD data. I have gone through the exercise of
trying to get agreement between scala and scalepack by optimizing
error model parameters ... though not yet with this particular
dataset. Keep in mind that these are nearly identical datasets
(actually the same Bragg reflections), so it is a relative
improvement figure and not absolute I/SIG that are relevant here.

I had not thought to go as far as density comparison. That's a good
idea. Unfortunately the datasets were kept incomplete on purpose to
reduce possible radiation damage effects.

Richard

On Nov 26, 2007, at 11:38 AM, Juergen Bosch wrote:

> Richard Gillilan wrote:
>
>>
>>
>> I am currently working on guidelines for when helium and
>> microbeam are necessary (based on both simulations and explicit
>> measurements). At the present time, my feeling is that crystals
>> below 50 micron can certainly make the extra hassle worthwhile.
>> It really depends upon how badly you want that extra resolution.
>> In the case above, it pushed the resolution from above to below
>> the 2.0 Angstrom mark based on I/SIG.
>>
> Hi Richard,
>
> I/SigI based on which program ? Default modes or tweaked by
> expert ? I would give this particular dataset a chance to be
> processed by all available programs and then do the comparison, or
> actualy all the datasets you have with various setups. Should be a
> nice table comparing program X versus Y and Z with the given data.
> And if it's SeMet data that would even be better - runnig e.g.
> Shelx and demonstrating which setup leads to an interpretable
> electron density.
>
> Juergen
>
> --
> Jürgen Bosch
> University of Washington
> Dept. of Biochemistry, K-426
> 1705 NE Pacific Street
> Seattle, WA 98195
> Box 357742
> Phone: +1-206-616-4510
> FAX: +1-206-685-7002
> Web: http://faculty.washington.edu/jbosch
>
>
>

CCP4bb navigation

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

Previous message:
Subject: Re: To bathe or not to bathe.
From: "Nave, C (Colin)" colin {- dot -} nave {- at -} DIAMOND {- dot -} AC {- dot -} UK
Date: 2007-11-26

Next message:
Subject: Two postdoc positions in Structural Biology--University of Pittsburgh
From: Peijun Zhang pez7+ {- at -} PITT {- dot -} EDU
Date: 2007-11-26