An ice-contaminated ring decorrelates its reflections, so its merged half-set
CC1/2 falls well below the Bragg trend of its resolution shoulders (e.g.
EP_cs_01-17 2.25A ring CC1/2 0.12 vs shoulders 0.89). After the final merge,
compute per-hexagonal-ice-ring CC1/2 in the ring band (+/- ice width in q=2pi/d)
against the shoulders either side, mask any ring more than 0.05 below its
shoulders (reliable shoulder CC1/2 > 0.5, >=20 reflections each) and re-merge
without them. Weak/absent rings track their neighbours and stay, so clean
crystals are untouched.
Data-driven and robust on /data/rotation_test: 16/18 crystals mask nothing and
are unchanged (every clean crystal, plus icy-but-fine EP_cs_02-10); EP_cs_01-17
masks 6 rings, CC1/2 6.9% -> 28%; CQ066/pding4_003 mask one marginal ring each.
A well-scaled CC1/2 test, replacing the fragile per-image azimuthal cutoffs.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
leonarski_fandClaude Fable 5
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