As Eleanor and Gerard explained - perhaps there is a reason that some frames are really bad.
But it could just as well be that the crystal diffracts anisotropically, and those frames with high Rmerge correspond to a weak region of reciprocal space. In this case, it would be quite counterproductive to remove them, since the best you can do is to increase the multiplicity, which should lead to improved accuracy of the data.
The program xdscc12 allows you to find out the influence of frames on the CC1/2 in a user-specified number of resolution range. This would tell you if those frames deteriorate your merged data, or not. Rmerge is the wrong value to look at.
best,
Kay
On Thu, 9 Nov 2017 14:04:36 -0500, CPMAS Chen <[log in to unmask]> wrote:
>Hi All,
>
>Is there a way to reject diffraction images based on Rmerge?
>
>When I processed my data with XDS, I use AIMLESS in CCP4 to get merged,
>truncated data. However, there is quite some images with high Rmerge, say
>larger than 1. Is there a keyword I can use to reject these images based a
>Rmerge cut-off, say 0.6?
>
>Thanks!
>
>Charles
>
>--
>
>***************************************************
>
>Charles Chen, Ph. D
>
>Research Associate
>
>University of Pittsburgh School of Medicine
>
>Department of Anesthesiology
>
>******************************************************
>
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