MeerK40t calibration scan report - s2 - 2026-10-31 22:13:25 CDT
burned with: lens_size 133.509 mm, flip_x False, flip_y True, swap_xy True, rotate 0, cor /tmp/mkcal_selftest/s1_corrected_L133.509.cor
scan: snipped corner found at scan BR; rotating scan 180 deg CCW so it is top-left; marks LIGHTER than paper; 1464 points; pips 12/12

ORIENTATION: burn appears correct (not mirrored, not rotated)
  -> no flip/swap change needed
SCALE: X +0.025 %   Y -0.020 %   mean +0.003 %  (+ = burn too big)
  centre-line rulers X +0.017 %  Y -0.012 % ;  square edges X +0.040 %  Y -0.034 %
  -> MeerK40t Lens Size: 133.509 -> 133.512 mm   (only global-scale knob MeerK40t has)
SKEW: -0.0059 deg (angle between burned X and Y axes minus 90)
TRAPEZOID: top-bottom +0.012 %   left-right +0.049 %
  outer square sides (nominal 100, rotation removed): top 100.046 bottom 100.034 left 99.99 right 99.941
BOW of outer sides (mm, + outward = barrel, - inward = pincushion): {'top': 0.01, 'right': -0.016, 'bottom': 0.012, 'left': -0.006}
CENTRE: cross is [-0.006, 0.001] mm (x,y) from the outer-square centre
CIRCLE circle_big: nominal 70.0 -> 70.014 x 69.99 mm (ovality 0.023 at 102.2 deg)
CIRCLE circle_centre: nominal 15.0 -> 14.998 x 14.996 mm (ovality 0.002 at 91.0 deg)
CIRCLE circle_corner_BL: nominal 8.0 -> 8.005 x 7.992 mm (ovality 0.012 at 94.0 deg)
CIRCLE circle_corner_BR: nominal 8.0 -> 8.005 x 7.987 mm (ovality 0.018 at 88.6 deg)
CIRCLE circle_corner_TL: nominal 8.0 -> 8.002 x 7.994 mm (ovality 0.007 at 115.5 deg)
CIRCLE circle_corner_TR: nominal 8.0 -> 8.007 x 7.989 mm (ovality 0.018 at 87.0 deg)
RULER tick errors after best similarity fit (mm): {'x-44': -0.007, 'y-44': -0.003, 'x-30': -0.018, 'y-30': 0.019, 'x-20': -0.024, 'y-20': 0.016, 'x-10': 0.01, 'y-10': 0.013, 'x+10': -0.008, 'y+10': 0.004, 'x+20': -0.015, 'y+20': 0.002, 'x+30': 0.015, 'y+30': -0.004, 'x+44': -0.015, 'y+44': -0.024}
MARK STRENGTH by region (weak-corner check): {'TL': 90.3, 'TR': 90.4, 'BL': 90.0, 'BR': 90.3, 'centre': 90.4}
FIT RMS (mm): {'rigid': 0.0141, 'similarity': 0.0141, 'affine': 0.0111, 'cubic': 0.0098}
WORST POINT (mm, inside the 100 mm square): rigid-only 0.043 ; after lens fix only 0.043
PREVIOUS CORRECTION RESPONSE gamma = 1.043 (1.0 = correction acted exactly as predicted; ~0 = ignored/transposed; <0 = SIGN INVERTED)
NEW .cor: /tmp/mkcal_selftest/s2_corrected_L133.512.cor  (max table change 17.9 ticks, gain 0.96, sign +1)
  half-strength alternative: /tmp/mkcal_selftest/s2_corrected_L133.512_half.cor
  after selecting this .cor in MeerK40t the GUI resets Lens Size to 125.002 - type 133.512mm back in