Testing the first version on ILCE-7RM4 photos found a partly clipped sky between
bare branches leaning cyan to teal under #523's edit, where Lightroom shows white.
Where only green clipped, red and blue say such a sky is a pale cyan-blue; the
rebuild kept that colour until halfway to full clipping, and darkening and a camera
profile showed it. Colour borrowed from another surface (bright foliage below the
sky) could also push green up, with a small step where green first clips.
- highlight::reconstruct_with: the colour of a pale partly clipped pixel
(saturation relative to the colour model's white below 0.2, easing off by 0.4)
fades to the clipped neutral from the first clip on instead of from halfway;
brightness and strongly coloured pixels keep the old schedule.
- Borrowed colour counts less and less as both the pixel's own channels and the
rim's colour contradict it (0.15 to 0.4 stop); either alone can be wrong.
- Right past the rim every estimate continues the rim's colour (it used to hold
the clipped channels at their clip, for the neutral estimate only), so the first
clip has no step whatever lent the estimate. The rim is built whenever there is
clipping.
- Nothing jumps where a later channel clips: in the rim distance and the
contradiction, a clipped channel counts as the lower bound it is, and a channel
goes over to that from 0.75 of its clip; a channel about to clip is a floor
capped like the clip floor it becomes.
- Tests: a pale sky above yellow-green foliage with thin dark branches in it (no
step where green clips, no green from the foliage, the same beside the branches,
neutral well past the clip); the fringe test compares the sky beside the branch
with the sky away from it, on its way to neutral; a band whose red clips second
next to a rim of another colour renders without a step, in six layouts.
- docs/parity.md: the Highlights note. Render cache version 28.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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