Re: [ccp4bb]: MIR phasing

[Jim Pflugrath <jwp@RigakuMSC.com>]

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> I have played with these numbers already. yet i could see too many
> peaks in the the calculated default Harker map sections. The
> diffraction symmetry shows
>...

When looking for peaks in a Harker section of a Patterson map sigma is
not always good criteria for significance.  Your putative derivatives
could be non-isomorphous and you could have the results you see.

What I like to suggest, is to contour your Harker sections with both
positive and negative contours.  If your most negative hole is -6 sigma,
then that's the noise level in your section.  Any significant
peaks will be above +6 sigma and probably above +12 sigma.  It's just that
the first value of sigma was not that meaningful.