ScaleOnTheFly fits each frame's scale G independently with no neighbour
coupling, so the few partials of one rocking event are weight-summed in
combine3D on inconsistent scales - jitter that never enters the full's
counting sigma and instead surfaces as scatter between symmetry mates,
inflating the error-model b (low ISa). A centered moving average of
log(G) over a small frame window (default 9, on for rot3d) removes it,
mirroring XDS's smooth scaling. Complementary to --scale-fulls (which
rescales between fulls, after the combine): smoothing fixes within-event
scale, scale-fulls fixes between-full.
On the rotation lysozyme set (1.4A, merged, with --scale-fulls): ISa
11.7 -> 15.0, R_meas 10.0% -> 8.3%, CCref stable, chi2 ~0.97 (honest).
Anomalous (full-res): ANODE S-peak 0.61x -> 0.80x of XDS.
--smooth-g[=window] tunes/disables it (=0 off); --mosaicity <deg> is a
diagnostic that fixes the scaling mosaicity for sweeps.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
leonarski_fandClaude Opus 4.8
99b923e727