Commit Graph
5 Commits
Author SHA1 Message Date
dtourolle 3f8f909e41 Make the colour mixer's saturation reach muted colours
Every photograph with a colour-mixer saturation edit now renders differently:
a raised band is stronger, most of all on muted colours.

The mixer matched bands and judged saturation on scene-linear values, and
scaled chroma by the same factor whatever a colour started at. Against the
photographer's earlier exports of two looks (~90 photographs, their raws, by
encoded hue), a sky band raised by 58 there lifted muted sky blues about
2.1×; here the mixer gave 1.15×, and less in the muted tones that carry most
of a sky or a shadowed snowfield.

Bands are now matched and saturation judged on display-encoded values. A
raised band pushes muted colours hardest and tapers to nothing at full
saturation, at a gain of 3.0, which at the same value lifts muted sky blues
about as those exports did. Lowering saturation still scales every colour
alike. Hue shifts work on the same encoded colour; luminance still scales in
linear light.

The bundled presets that use the mixer, and those whose colour was tuned
against the default rendering, are rescaled to the amount of colour they
had: Vivid 1.30, Vivid warm 1.30, Vivid landscape 1.38, Vivid, strong 1.45,
Vivid portrait 1.15, Punch 1.12, Blue sky 1.08, Deep blue sky 1.12, Polariser
1.26, Blue sky, golden land 1.13 — mean CIELAB chroma over the default
rendering, on 30 raws from the library. Negative values (skin protection)
are left as written.
2026-10-04 05:28:22 -04:00
dtourolle 25dc0d0179 Give the Vivid presets and Punch measured amounts of colour
On the default rendering, Vivid added 22 % more chroma than the rendering
itself, and Punch 5 % — less than the photographer's earlier exports show
with no look applied (14 % over ours) and well below their everyday look
(27 %). Each preset's colour values (vibrance, saturation, the mixer's
saturation bands) are now scaled together, tone values untouched and
negative ones — Vivid portrait's skin protection — left as written, until
the preset measures: Vivid and Vivid warm 1.30, Vivid landscape 1.38, Vivid,
strong 1.45, Vivid portrait 1.15, Punch 1.12. Measured as mean CIELAB chroma
over 30 raws from the library, as a ratio to the default rendering.
2026-10-03 23:04:46 -04:00
dtourolle 8294e6b59f Call the reference curve what it is, and drop wording that reads as copying
The view transform's second curve is the DNG SDK's published reference
rendering — the ACR3 default curve applied by RefBaselineRGBTone — so
it is the "DNG Reference" curve in the panel, D21 and the code, not a
name borrowed from another product. Comments and docs that justified a
choice by another editor doing it ("as their Amount", "so a
photographer arriving from it finds the name") now give the actual
reason. The Vivid presets no longer describe themselves as reaching
for another editor's look; they are DarkRoom's own.

Factual mentions stay: which program wrote the library's DNGs, what
was measured against, and preset import. camera-profiles.md gains §15,
on starting a photograph from the edit it already carries.
2026-10-03 14:22:49 -04:00
dtourolle 54772f94d6 Correct what D20 claimed the profile tables would do for colour
Measured after building them, on four of the library's 6D DNGs: Adobe
Standard's tables lower mean saturation by 3-9 % at defaults, and the
look at 200 % lowers it further. The 6D's look table scales saturation
by 0.925 in its darkest value rows; it was tuned to sit under Camera
Raw's default RGB tone curve, which DarkRoom does not apply, and the
dark-tone desaturation is what is left without it. On _MG_9080 the
Lightroom preview measures 0.49, the matrix alone 0.38, the profile
0.35.

So the spec's "that gap is most of why the same file looks flatter"
was wrong: the gap is tone. The tables stay — they put each hue where
Adobe put it — and the spec, D20 and the Vivid file now say so.
"Stronger camera look" is removed: a stronger Adobe Standard look is a
less saturated picture, the opposite of its name. The Vivid presets,
measured at 0.40-0.46 on the same frame, are what answers "more
colourful" today.
2026-10-02 22:38:07 -04:00
dtourolle cb7ad0bbe7 Ship a Vivid section of presets
Five looks for "more colourful than the default": Vivid, Vivid strong,
Vivid landscape, Vivid warm and Vivid portrait. They lean on vibrance,
which lifts muted colours most and holds skin back, and use saturation
sparingly on top; landscape and portrait work the colour mixer's bands
so foliage and sky get richer while skin does not. A sixth, Stronger
camera look, pushes the camera profile's look table to 175 %, about the
step from Adobe Standard to Adobe Vivid, and only moves vibrance where
a photograph has no profile.

All change only what they name, so they keep a corrected exposure or
white balance, and the shipped-preset tests bound every key and value.
2026-10-02 22:38:07 -04:00