Lightroom → chemigram cheat sheet¶

"Where do I find X?" mapping for users coming from Lightroom. v1.8.0 ships 51/52 daily-use Lightroom controls (98%); the remaining gap is documented at the end. Each Lightroom control maps to a CLI invocation + MCP tool example, plus notes on what's different.

For the underlying state of what's covered, see capability-survey.md § 13. This guide is the "I know Lightroom; show me chemigram" view of the same surface.

Quick orientation¶

Lightroom's Develop panels map onto chemigram's three-layer vocabulary (per docs/concept/03-data-catalog.md):

Lightroom panel sliders → L3 primitives (single-module, parameterized or discrete .dtstyle entries)
Lightroom presets → L2 looks (multi-module composites)
Lightroom workspace settings (camera profile defaults) → L1 baselines (camera-specific templates)

Every Lightroom slider is one CLI invocation. The general shape:

chemigram apply-primitive <name> --image <id> [--value <V> | --param NAME=V ...]

Or via MCP:

apply_primitive(name="<entry_name>", image_id="<id>", value=V, parameters={...})

Panel: Light¶

Lightroom	chemigram	Notes
Exposure	`apply-primitive exposure --value V`	Range [-3.0, 3.0] EV.
Contrast	`apply-primitive sigmoid_contrast --value V`	Sigmoid-based; range [0.5, 5.0]. 1.5 = no-op.
Highlights	`apply-primitive highlights_clip_threshold --value V`	Or `apply-primitive toneequalizer --param highlights=V` for the 9-band approach.
Shadows	`apply-primitive toneequalizer --param shadows=V`	Or the mask-bound `gradient_bottom_lift_shadows`.
Whites	`apply-primitive toneequalizer --param whites=V`	Or discrete `whites_open`.
Blacks	`apply-primitive toneequalizer --param blacks=V`	Or discrete `blacks_lifted` / `blacks_crushed`.
Tone Curve	❌ Not yet shipped	Tracked as #94; needs darktable-GUI baseline capture session.

Coverage: 6/7.

Worked example¶

Lightroom: "Lift the shadows by +20." chemigram: chemigram apply-primitive toneequalizer --param shadows=0.2 --image DSCF1234

Lightroom: "S-curve the contrast." chemigram: chemigram apply-primitive sigmoid_contrast --value 1.8 --image DSCF1234

Panel: Color¶

Lightroom	chemigram	Notes
WB Temp (Kelvin)	`apply-primitive wb_kelvin_delta --param kelvin_delta=V`	Range [-3000, +3000] K. Positive = warmer. Linear approximation; for raw RGB control use `temperature` directly.
WB Tint	`apply-primitive wb_kelvin_delta --param tint_delta=V`	Range [-200, +200]. Positive = magenta.
Vibrance	`apply-primitive vibrance --value V`	Range [-1.0, +1.0].
Saturation	`apply-primitive saturation_global --value V`	Range [-1.0, +1.0].

Coverage: 4/4.

The raw temperature entry is also available for users who want to set red/green/blue coefficients directly: apply-primitive temperature --param red_coeff=V --param green_coeff=V --param blue_coeff=V. The wb_kelvin_delta entry is the photographic-units wrapper; both ride the same underlying decoder.

Panel: Color Mixer (HSL)¶

Lightroom's HSL Color Mixer = 24 sliders (Hue / Sat / Luminance × 8 colors). All shipped via colorequal (RFC-023).

Lightroom	chemigram
HSL Hue per color	`apply-primitive hsl_hue --param hue_<color>=V`
HSL Saturation per color	`apply-primitive hsl_saturation --param sat_<color>=V`
HSL Luminance per color	`apply-primitive hsl_luminance --param bright_<color>=V`

Colors: red, orange, yellow, green, cyan, blue, lavender, magenta (Lightroom calls them red / orange / yellow / green / aqua / blue / purple / magenta).

Hue is in degrees [-180, +180]; sat / luminance are normalized [-1.0, +1.0].

Coverage: 24/24.

Worked examples¶

Lightroom: "Make the sky deeper." chemigram: chemigram apply-primitive hsl_luminance --param bright_blue=-0.3 --image DSCF1234

Lightroom: "Warm up the foliage (shift greens toward yellow)." chemigram: chemigram apply-primitive hsl_hue --param hue_green=15.0 --image DSCF1234

Lightroom: "Mute the orange skin tones slightly." chemigram: chemigram apply-primitive hsl_saturation --param sat_orange=-0.1 --image DSCF1234

Panel: Color Grading¶

Lightroom's Color Grading panel = per-zone hue / saturation / luminance + global blending + balance.

Lightroom	chemigram	Notes
Shadows: hue	`apply-primitive hue_shadows --value V`	[0, 360]°. Or discrete `grade_shadows_warm` / `grade_shadows_cool`.
Shadows: saturation	`apply-primitive saturation_shadows --value V`	[-1.0, +1.0]
Midtones: hue	`apply-primitive hue_midtones --value V`	Or discrete `grade_midtones_warm` / `grade_midtones_cool`.
Midtones: saturation	`apply-primitive saturation_midtones --value V`
Highlights: hue	`apply-primitive hue_highlights --value V`	Or discrete `grade_highlights_warm` / `grade_highlights_cool`.
Highlights: saturation	`apply-primitive saturation_highlights --value V`
Global: hue rotation	`apply-primitive hue_angle --value V`	Rotates all pixels uniformly.
Per-zone luminance	`apply-primitive brilliance_<zone> --value V`	`brilliance_shadows` / `brilliance_midtones` / `brilliance_highlights` / `brilliance_global`.
Blending	`apply-primitive shadows_weight --value V` + `highlights_weight --value V`	Falloff between zones.
Balance	`apply-primitive white_fulcrum --value V`	Shifts the shadow/highlight midpoint.

Coverage: 7/7 (counting the panel as a whole).

Quick split-tone¶

Lightroom: Apply a teal-orange split toning preset. chemigram: chemigram apply-primitive grade_split_warm_cool --image DSCF1234 (a discrete L3 entry combining grade_shadows_cool + grade_highlights_warm in one move; #110).

For full cinematic looks, see L2 looks below.

Panel: Effects¶

Lightroom	chemigram	Notes
Texture	`apply-primitive texture --param first=V`	Via darktable's `diffuse-or-sharpen`. Negative smooths fine detail; positive enhances.
Clarity	`apply-primitive bilat_clarity_strength --value V`	Bilateral local contrast. Range [-1.0, 4.0]. Discrete kinds also: `clarity_painterly`, `clarity_etched`, `clarity_dreamy`.
Dehaze	`apply-primitive dehaze --param strength=V`	Range [-1.0, +1.0]. Negative adds haze.
Vignette	`apply-primitive vignette --value V`	Range [-1.0, +1.0]. Discrete kinds: `vignette_subtle`, `vignette_strong`.
Grain	`apply-primitive grain_strength --value V`	Range [0.0, 100.0].

Coverage: 5/5.

Panel: Transform¶

Shipped via the ashift module (#101).

Lightroom	chemigram
Rotate (degrees)	`apply-primitive transform --param transform_rotation=V`
Vertical perspective (keystone)	`apply-primitive transform --param transform_lensshift_v=V`
Horizontal perspective	`apply-primitive transform --param transform_lensshift_h=V`
Shear	`apply-primitive transform --param transform_shear=V`
Aspect adjust	`apply-primitive transform --param transform_aspect=V`

Coverage: 5/5.

Lightroom's "Auto" transform option (auto-detect verticals / horizontals from image content) is not yet shipped. Manual rotation works fine; auto-detection would need a sibling provider per the BYOA principle.

Panel: Detail¶

Lightroom	chemigram	Notes
Sharpening (Amount)	`apply-primitive sharpen --value V`	Range [0.0, 2.0]. Discrete kinds: `sharpen_edge_only`, `sharpen_overall`.
Sharpening (Radius / Detail / Masking)	Not directly exposed	Sharpen module's defaults handle these; if you need custom values, hand-author a discrete entry.
Noise Reduction (Luminance)	`apply-primitive denoise --param denoise_strength=V`	NLMEANS mode. Range [0.001, 1000.0]. Wavelet-mode fallback tracked as #100 task C.
Noise Reduction (Color)	Implicit in denoise	darktable's denoiseprofile handles luminance + chroma noise together.

Coverage: ~2/4. Lightroom's separate Sharpening Radius / Detail / Masking sliders aren't exposed as parameters; chemigram pins them at darktable defaults. If you need them, hand-author a discrete sharpen variant.

Panel: Lens Corrections¶

Lens correction shipped via the lens module (#95). Photographic effect requires populated lensfun identifier strings — see #100 task B for the EXIF auto-binding follow-up.

Lightroom	chemigram	Notes
Profile-based correction	`apply-primitive lens_correction`	Uses lensfun via `camera`/`lens` strings. Currently empty — populated when EXIF auto-binding lands.
Distortion (manual)	`apply-primitive lens_correction --param lens_cor_distortion=V`	Range [0.0, 1.0].
Defringe (CA)	`apply-primitive lens_correction --param lens_tca_r=V --param lens_tca_b=V`	Manual TCA shift; 1.0 = no shift.
Vignette correction	`apply-primitive lens_correction --param lens_v_strength=V`	Manual override; range [-1.0, 1.0].

Panel: Camera Calibration¶

Mostly handled by darktable's input color profile. Manual primaries-tuning isn't exposed as a chemigram primitive today; if needed, hand-author a discrete colorin entry.

Lightroom presets → chemigram L2 looks¶

Lightroom users typically reach for preset packs (Adobe / VSCO / Mastin Labs / etc.). chemigram ships 13 L2 looks covering the most common photographic recipes:

Cinematic / film genre: - look_cinematic_teal_orange — Hollywood blockbuster - look_film_kodachrome — Saturated reds, warm midtones - look_film_portra — Kodak Portra 400 portrait - look_vintage_film — Faded film aesthetic

Portrait: - look_portrait — Gentle skin-protective default - look_high_key_portrait — Bright, soft, lifted - look_low_key_portrait — Dark, dramatic, crushed - look_moody_dramatic — High contrast, desaturated

Decade: - look_70s_film — Warm, golden, medium grain - look_90s_grain — Heavy grain, slightly cool - look_2000s_digital — Clean, oversaturated

Landscape / neutral: - look_landscape — Vibrant dramatic - look_neutral — Teaching baseline (starter pack)

Apply any of them with:

chemigram apply-primitive look_<name> --image <id>

The visual-proof gallery shows each look applied to the synthetic ColorChecker chart: see docs/guides/visual-proofs.md.

Lightroom features chemigram doesn't yet have¶

Lightroom feature	chemigram status	Tracked as
Spot removal / heal	✅ Shipped v1.9.0	`apply_spot` MCP tool / RFC-025 / ADR-087
AI subject mask	✅ Shipped v1.9.0 (LLM-vision; conversation-native)	RFC-026 / ADR-086 + `mask_subject` named mask (RFC-032)
Adaptive Sky preset	✅ Shipped v1.10 (parametric fallback + LLM-vision escalation)	`mask_sky` named mask (RFC-032) + Pattern 7 of `llm-vision-for-masks.md`
Range masks (color-range, luminance-range)	✅ Shipped v1.9.0	RFC-024 / ADR-085; named-mask vocabulary in RFC-032
Capture One Skin Tone Uniformity	✅ Shipped v1.10 (color-band uniformity; texture deferred)	`skin_uniformity` entry / RFC-033
Frequency separation (skin smoothing)	⚠️ Approximated v1.10 (`skin_smooth_painterly` via masked clarity reduction); true band decomposition deferred	RFC-033 Portrait Gap #4
Batched dodge-and-burn	✅ Shipped v1.10 (atomic N-region apply)	`apply_per_region` MCP tool / RFC-031
Tone Curve (parametric / point curve)	Not shipped	#94; needs darktable-GUI baseline session
HSL precision via Range slider	Not shipped (95% covered via colorequal)	#98 colorzones spline-curve fallback
Profiled lens auto-correction (EXIF-bound)	Decoder shipped; auto-bind pending	#100 task B
Auto-Tone / Auto-WB	Not shipped	The BYOA arc — sibling project shape per ADR-007
Camera Calibration primaries-tuning	Not exposed as primitive	Hand-author `colorin` discrete entry if needed

When chemigram differs (and why)¶

WB Kelvin: chemigram exposes kelvin_delta (relative shift) instead of absolute Kelvin. The mapping from absolute Kelvin to RGB coefficients is camera-specific (depends on primaries). Linear approximation is daily-use accurate; perfect chromatic adaptation (CAT02 / Bradford) is out of scope for the UX wrapper.
HSL backing module: chemigram uses darktable's modern colorequal mv4, not the older colorzones. ADR-083 records the choice. Trade-off: 95% of HSL workflow works perfectly; the remaining 5% (per-zone Range slider falloff curves) is tracked as #98.
Vocabulary growth: Lightroom presets are user-installed. chemigram's vocabulary growth is use-driven: the agent logs gaps via log_vocabulary_gap when it reaches for a missing primitive; the photographer or maintainer then authors the missing entry. See docs/guides/gap-log.md and CLAUDE.md's Phase 2 framing.
Agent loop vs. direct manipulation: chemigram is agent-first. Mode A loops are the canonical interaction. The CLI exposes the same surface for direct invocation, but the design optimizes for agent reasoning (taste / brief / notes / session transcripts) more than slider-by-slider iteration.