colorIndexToRgb maps a B−V onto the star field's tint ramp, and its one caller passed it every
star's colour index, whatever colorSystem said. BP−RP is the larger of the two for the same star —
0.823 against 0.65 for a G2 dwarf, 1.84 against 1.42 for an M0 (Pecaut & Mamajek) — so the 376 703
stars measured in it, 83 % of the catalogue, were tinted as later types than they are, and redder
than HYG's stars of the same type, and than their own disc in the system view.
A BP−RP is now carried to the B−V of the dwarf sequence at that colour (the table's own B−V
column, which DwarfSequencePoint now returns, clamped at its ends), then tinted as before. The
median Gaia colour, BP−RP 0.883, a G7 dwarf, read as a K2: its tint goes from (1, 0.972, 0.955) to
(0.975, 0.982, 1), the same as HYG's G7 stars.
Controls, each failing its named test: BP−RP read as B−V (2 of 792 failed), the star field not
passing the colour system (1 of 792), and the B−V taken from the wrong column (3 of 792).
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
SenrokaiandClaude Opus 5.5
4191b70e63