MINIMUM ZETA

As always, the authoritative documentation is at http://www.mpimf-heidelberg.mpg.de/~kabsch/xds/html_doc/xds_parameters.html#MINIMUM_ZETA= !

What is MINIMUM_ZETA?

MINIMUM_ZETA is a parameter determining how close reflections may be to the 'blind region' of reciprocal space to still be integrated. On the detector, the blind region consists of two cones starting at the direct beam position, and extending into the spindle direction.

A high value (corresponding to a large blind region) is "safe" but produces lower completeness because more pixels of the detector are considered to be in the blind region. The default of 0.15 is on the safe side. I routinely use 0.1, and 0.05 turns out to still be good.

How could I check if a low value of MINIMUM_ZETA is beneficial for my data reduction?

It does not hurt to use a low value of MINIMUM_ZETA (e.g. 0.05) in INTEGRATE, because in CORRECT you may still choose a higher value (i.e. you don't then have to re-run INTEGRATE if you want to test a different value).

Then, run CORRECT with higher values and see how this changes completeness and R-factors.

For a finer evaluation, you might want to inspect the plot rf.pck of XDSSTAT .