Perpendicular Buffalo Thunderbird

The perpendicular Buffalo cross x' = |x^2 - y^2| + a, y' = -2x|y| + b iterated over the parameter plane, framed on its mini-set on the western antenna near c = -1.76154 - 0.00121i. Neither fold is holomorphic, so the distance estimate rides the exact real 2 by 2 Jacobian carried in log-scaled form. Three fields drive the colour, the distance ridge as luminance, the smooth count across a storm violet to white lightning ramp, and a stripe average as a hue shift.