Fujifilm's nine-knot distortion and vignetting tables (knots at sqrt(k/8))
end at the corner on the eighth knot; the ninth, sqrt(9/8), lies past it
with the eighth's value repeated. Reading them at rho = knot_last * r took
every value from 6 % further out. On the X-T4 the warp polynomial then
failed its fit checks on 253 of 425 zoom-lens raws, which got no
distortion correction at all, and corners came out up to 6.5 % brighter
than the camera's. Read at rho = r, the tables match the camera's measured
geometry and corner gain (docs/fuji-lens-corrections.md, "Knot radius").
Nothing changes for the 11-knot and 8-knot tables, whose last knot is 1.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
