Re: [ccp4bb] How to reduce no. of overlaps

- Protein crystallography

Main steps:

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

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Subject: Re: How to reduce no. of overlaps
From: Zhijie Li zhijie {- dot -} li {- at -} UTORONTO {- dot -} CA
Date: 2012-03-07

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Subject: Re: How to reduce no. of overlaps
From: Frank von Delft frank {- dot -} vondelft {- at -} SGC {- dot -} OX {- dot -} AC {- dot -} UK
Date: 2012-03-07

Subject: Re: How to reduce no. of overlaps
From: Jim Pflugrath Jim {- dot -} Pflugrath {- at -} RIGAKU {- dot -} COM
Date: 2012-03-07

In addition to reducing the beam divergence, you may wish to use a smaller beam size by using a smaller collimator or making the slits smaller. A smaller crystal can also help to spatially separate the Bragg spots as can moving the detector closer to the crystal. Yes, closer to the crystal. This is not intuitive, but arises since modern homelab beams are not parallel but are diverging from a focal point near the sample position. It is just something else you may wish to try.

How you flashcool your sample will also have a large effect on the spot sizes/shapes.

Jim

>.....
>Another thing: most in-house sources allow you to reduce divergence of the beam. You lose intensity, >but no matter, just expose longer. That also improves overlap.
>
>Cheers
>phx

CCP4bb navigation

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

Previous message:
Subject: Re: How to reduce no. of overlaps
From: Zhijie Li zhijie {- dot -} li {- at -} UTORONTO {- dot -} CA
Date: 2012-03-07

Next message:
Subject: Re: How to reduce no. of overlaps
From: Frank von Delft frank {- dot -} vondelft {- at -} SGC {- dot -} OX {- dot -} AC {- dot -} UK
Date: 2012-03-07