Since there has been mention of putting data from XDS into Pointless,
I should say that I have made yet another (!) fix today for reading
XDS data. It now flags & ignores reflections marked as MISFITS in the
XDS file (marked with SD < 0). Previous versions included these
reflections which at least in one case that Graeme Winter sent me
gives very bad results if they are included.
Fixed in version 1.2.14
ftp://ftp/mrc-lmb.cam.ac.uk/pub/pre/pointless-1.2.14.linux
ftp://ftp/mrc-lmb.cam.ac.uk/pub/pre/pointless-1.2.14.tar.gz
Pointless will read either XDS_ASCII.HKL files (MERGE=FALSE) or
INTEGRATE.HKL, and will score possible point groups and space groups.
It will also generate a file which can go into Scala, should you
believe that Scala does a better job than XSCALE (I have no particular
reason to suppose so)
Kay mentioned the MODULATION correction in XDS. Recent versions of
Scala (from 3.2.31) contain a CORNER_CORRECTION option which applies a
precalibrated table of detector corrections: tables are specific for
each detector, and are available I believe for the ESRF detectors. As
far as I understand the XDS correction is different in that it is
determined from the data itself (so it doesn't require a table to be
available), but it should achieve the same end. It is not clear to me
at present how important this is, but the correction can be quite
large near the corners of a tiled CCD.
Phil
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