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After a successful run of NODIRAX, the program should
end with a list of at least 40-50 ndlvs. All major conics
of the observed pattern should be found by the program. If the
program either did not find enough conics, and/or missed some
main conics, try the following steps (in order of importance):
- Check the beam center. See the previous section.
- Check the crystal-detector distance.
- Check the number of cycles specified by ncycle.
Increase the more of cycles (3).
- Reduce the minimum number of spots that the final conics should
have, as specified by mincon.
- Pick more spots using the peak-search algorithm of the xdisp
program.
- Reduce the number of steps and/or the step size in the process of
expanding and combining planes, as specified by nrspot.
- Reduce the value of qmin. Try values
like 0.2, 0.1, 0.05 and 0.01.
- Increase the expected root-mean-square distance between the
predicted and refined spot positions, using sigma.
We normally use values like 0.2 for FUJI image plates and 0.1 for the
ESRF CCD detector.
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