The stills merge had no working outlier rejection. --reject-outliers was 0 for stills, and when set its
band took the systematic part as a factor exp(+-n s), s the spread of ln(I / median) - on stills a
reflection's observations are partials and per-crystal scales, many near zero, so s is wide and the band
let through observations hundreds of sigma out. On a high-multiplicity broad-bandpass run with a spotty
powder contaminant, single grains in a weak reflection's box were that reflection's whole merged
intensity (half-set means -2 vs 2284 on 141 observations); the shells holding the powder rings and the
lowest shell merged at CC1/2 0.6-0.75 beside 0.99 elsewhere, at multiplicity ~400-1000.
Stills now test the plain linear band, n sqrt(a sigma^2 + (b <I>)^2) about the median - the error
model's b is the spread as it is - at n = 10 by default (rotation keeps 6 and its multiplicative band).
The stills merge statistics now report the rejected count (OBSERVATIONS_REJECTED was always 0 there).
Measured (REFMAC 0-cycle R-free of an isomorphous room-temperature model, depositor's free set, scale
mode on stored integrations, vs the same code with --reject-outliers 0):
- broad-bandpass in-house stills, 50k frames: 0.318 -> 0.265; 20k: 0.274 -> 0.244; R_split 0.29 -> 0.06,
CC1/2 0.79 -> 0.98. 0.1% of the observations are rejected.
- monochromatic in-house stills, 30k frames: 0.216 -> 0.212; R_split 0.126 -> 0.087.
- n = 6 gains ~0.003 more there but costs the public XFEL sets 0.003-0.006 on three of four; 20 keeps
most of the gain.
Still battery, 12 non-float sets, against rc180: R_split better on all 12; R-free change mean -0.0005
(range -0.006..+0.003, plus pal86 +0.009 that is within that set's run-to-run spread of ~0.007 - a
rerun of rc180's behaviour gave 0.192 against the baseline's 0.185); one draw becomes a win (lcls242_s),
nothing else changes class. Rotation is untouched (the stills band and default are gated on the
experiment not being a rotation).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015CeEGgpKdfkCTJb3YNMJcu
(cherry picked from commit 3a7142801056f21c720956255f1207e0bf1a8f43)
leonarski_f
cf7676f5d5
