XDS.INP: Difference between revisions

211 bytes added ,  31 January 2016
m (Misspelling of ORGX as ORGY -- happens several times)
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;[http://www.mpimf-heidelberg.mpg.de/~kabsch/xds/html_doc/xds_parameters.html#REFINE(IDXREF)= REFINE(IDXREF)]
;[http://www.mpimf-heidelberg.mpg.de/~kabsch/xds/html_doc/xds_parameters.html#REFINE(IDXREF)= REFINE(IDXREF)]
:The defaults (REFINE(IDXREF)=DISTANCE BEAM ORIENTATION CELL AXIS i.e. refine everything) are OK, but '''only if''' COLSPOT has seen '''all''' (or rather, a significant fraction of the) frames (see SPOT_RANGE below). If only a small SPOT_RANGE was used (which is not the best way, but possible), one should use REFINE(IDXREF)= AXIS BEAM ORIENTATION CELL . (The next thing to omit would be AXIS)
:The default (REFINE(IDXREF)=POSITION BEAM ORIENTATION CELL AXIS i.e. refine everything) could be used, but '''only if''' COLSPOT has seen '''all''' (or rather, a significant fraction of the) frames (see SPOT_RANGE below). If only a small SPOT_RANGE was used (which is not the best way, but possible), one should use REFINE(IDXREF)= AXIS BEAM ORIENTATION CELL . This is also a good choice because at modern beam lines the distance should be accurately known.
;[http://www.mpimf-heidelberg.mpg.de/~kabsch/xds/html_doc/xds_parameters.html#REFINE(INTEGRATE)=  REFINE(INTEGRATE)]
;[http://www.mpimf-heidelberg.mpg.de/~kabsch/xds/html_doc/xds_parameters.html#REFINE(INTEGRATE)=  REFINE(INTEGRATE)].
:The defaults (REFINE(INTEGRATE)=DISTANCE BEAM ORIENTATION CELL) could be modified by omitting DISTANCE, because one should assume that the distance is constant. This is particularly recommended if SPACE_GROUP_NUMBER=0 or 1. Furthermore, by fixing the distance one can better see from the results of the refinement whether the cell parameters are stable, or whether they change due to radiation damage. There are situations when one wants to reduce the number of parameters to be refined even more, see [[Optimization]].
:The defaults (REFINE(INTEGRATE)= POSITION BEAM ORIENTATION CELL) could be modified by omitting POSITION, because one should assume that the distance is constant. This is particularly recommended if SPACE_GROUP_NUMBER=0 or 1. Furthermore, by fixing the distance one can better see from the results of the refinement whether the cell parameters are stable, or whether they change due to radiation damage. An even more robust way is to omit CELL instead of POSITION. There are situations when one wants to reduce the number of parameters to be refined even more, see [[Optimization]].  
;[http://www.mpimf-heidelberg.mpg.de/~kabsch/xds/html_doc/xds_parameters.html#REFINE(CORRECT)= REFINE(CORRECT)]
;[http://www.mpimf-heidelberg.mpg.de/~kabsch/xds/html_doc/xds_parameters.html#REFINE(CORRECT)= REFINE(CORRECT)]
:The defaults (REFINE(CORRECT)=DISTANCE BEAM ORIENTATION CELL AXIS i.e. refine everything) are OK. For low resolution datasets the distance refinement may not be stable (i.e. refined distance differs more than a few mm from expected distance). In this case one should remove DISTANCE from the list.
:The defaults (REFINE(CORRECT)= POSITION BEAM ORIENTATION CELL AXIS i.e. refine everything) are OK. For low resolution datasets the distance refinement may not be stable (i.e. refined distance differs more than a few mm from expected distance). In this case one should remove POSITION from the list. If that is the case, one should also not refine POSITION in IDXREF and INTEGRATE.


== Keywords which affect whether indexing will succeed ==
== Keywords which affect whether indexing will succeed ==
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