lightcraft/docs/gaps.md

Gaps: where LightCraft falls short of Lightroom

Last reviewed: 2026-10-10 · Last updated: 2026-10-10 · Change: major (created; absorbs the checklist's Top gaps and the ROADMAP's honest assessment, re-ranked after a full re-measure) · Target: Adobe Lightroom Classic 15.5 / Lightroom 9.6

Every known shortfall, one entry each, ranked by user impact (how many Lightroom users hit it, and how hard it blocks them), then by effort. Agents pick work from the top (the first entry nobody is working on). When you close a gap, delete or shrink its entry, update its rows in parity-checklist.md, and the numbers in target-app-parity.md and ROADMAP.md if they move.

Hours are Opus 5.5 agent wall-clock hours (see target-app-parity.md). B marks a gap that blocks beta.

Ranked

#	Gap	Evidence	User impact	Hours	Doc
1 B	Camera colour is estimated, not measured (LR-PROF-CAMERACOLOR). Raws start from a per-file fit to the camera JPEG, 4 bundled profiles or 52 spectral matrices; others use a neutral matrix	ΔE vs camera JPEG 2.9–10 after fitting (raw-parity.md); 0 chart-calibrated models vs 1,500 Adobe Standard profiles	every raw shooter sees colour that is close but not Lightroom's; some get neutral-matrix colour	50–90	raw-parity
2 B	CR3 beyond three verified bodies (LR-IMP-FORMATS): CRX variants other than those verified on M50 / R100 / R8 fall back to the preview; CR3 sRAW / mRAW and HEIF CR3 too	measured: Canon is the largest bucket (33% of photographers) and its share whose camera fully works is the lowest of the big four, 72%; 17 of 22 popular Canon bodies write CR3, 2 verified (raw-parity.md)	+6.5 points of photographers whose camera works, the biggest single raw gain	25–45	raw-parity
3 B	Render fidelity unmeasured (LR-BEHAV-RENDER-FIDELITY): tone, highlights, texture / clarity / dehaze, NR and sharpening are tuned by eye	no side-by-side suite; a retune needs a new process version (only V1 exists)	edits imported from Lightroom look different; the look "isn't Lightroom's"	30–60	raw-parity, process-versions
4 B	Original-pixel detail at 100% (LR-VIEW-ZOOM, P0): the whole-image preview is capped (2,560 px default); compare, overlays and soft proofing lack sharp zoom windows (#323)	checklist row 🟡	checking focus, the first thing culling needs, isn't reliable on large files	8–15	ui-parity
5 B	AI masks: Subject, Sky, People, Background, Landscape are heuristics; Object / Describe run SAM 3 but its download has no mirror configured	crates/segment; ai-masks.md; MASK rows 67%	masking is how most Lightroom users edit today	40–70 + model decision	target-app-parity
6 B	Compressed ORF (every Olympus / OM body since ~2008)	measured: 66 of 78 Olympus / OM models preview-only; orf.rs refuses; OM bucket 3% of photographers, 3% of them fully work	+2.6 points; best gain per hour of any raw gap (~0.2)	8–15	raw-parity
7	Nikon High Efficiency NEF (HE / HE★ on Z 8, Z 9, Z 6III, Z f, Z50II, Z5II when set to HE)	named and preview only (#193); needs a pure-Rust JPEG XS decoder	+1.1 points (only shots taken in HE; lossless works on the same bodies); low gain per hour (~0.04), so not a beta blocker	20–40	raw-parity
8 B	No lens profile database (LR-EDIT-OPTICS-PROFILE): only DNG opcodes, RW2 in-file distortion and Sony ILCE-7RM4A distortion	Adobe ships 3,635 lens profiles; we never use them	distortion / vignetting correction is a default step for many	40–80 + calibration shots	raw-parity
9 B	Tests don't run in CI on macOS, Windows or Linux x64: only FreeBSD runs cargo test; the others build packages	.github/workflows/ (freebsd, packaging-lint, release, windows-arm64)	regressions reach users on the main platforms; cargo xtask ci runs only locally	6–12	target-app-parity
10 B	Per-model verification thin, plus cheap per-body decode fixes: 234 of 1,446 Adobe models verified (16%), ~40% of photographers on a verified body; Nikon 5 bodies verified, Canon 11. Cheap fixes: Z 6II packed 14-bit NEF (#769, PR #671), Sony A100 / F828 regression (#702), DSLR-A200…A390 / A850 12-bit ARW (#535)	measured: raw/coverage.tsv	per-body bugs (levels, crops, WB) surface only from users	25–45	raw-parity
11	Enhance: Raw Details, Super Resolution; AI denoise without shippable weights or X-Trans	ENH rows 0%; denoise Bayer only, RawNIND weights GPL and opt-in	Fujifilm users get no AI denoise; nobody gets it out of the box	30–60 + model decision	raw-parity
12	Content-aware / generative remove, detect distractions, reflections removal	REM rows 75%; patch synthesis missing	cleanup work goes back to Photoshop	25–45 (+ generative model)	target-app-parity
13	Lightroom catalog migration is one-way and approximate: unsupported Adobe profiles / AI settings archived, history kept as data	lightroom-catalog-import.md	switching users lose some looks	8–12	file-format-parity
14	HDR display (EDR / Windows HDR); HLG; HDR settings from crs XMP	HDR rows 70%; LR-VIEW-HDR-DISPLAY ⬜	HDR editing works blind on HDR monitors	12–25	hardware-parity
15	Print module: custom packages, printer colour management (contact-sheet PDF only)	LRC-PRINT rows	Classic users who print	25–40	target-app-parity
16	Map view, Book, Slideshow module, publish services	LRC-MAP / BOOK / SS rows ⬜	Classic users; publish services matter for Flickr / SmugMug workflows	60–100	target-app-parity
17	Tethered capture	⬜	studio photographers	25–45 + cameras	hardware-parity
18	Video: playback, trim, global edits, export	VID rows 0%	users who mix stills and clips	25–45	target-app-parity
19	Plug-in ecosystem: no Lightroom SDK equivalent (export / publish plug-ins, metadata plug-ins)	⬜	pro workflows built on plug-ins (LR/Enfuse, Jeffrey's exporters, Negative Lab Pro)	40–80 + owner decision	target-app-parity
20	Long-tail raw formats: compressed SRW, ARQ pixel shift, IIQ, Hasselblad compression, X3F, CRW, MRW, ERF, KDC, DCR, MEF, GPR, old FinePix	raw-parity.md	small user share each	45–85	raw-parity
21	Localization: 9 of 15 shipped languages partial (74–99% of catalog messages), lower-layer errors English; Hindi, Arabic, Indonesian, Korean, Vietnamese absent; no RTL or complex shaping	measured from catalogs	non-English users see mixed English	55–90 (shipped to full); 145–255 (five new)	localization-parity
22	Pen pressure, OS monitor profiles, follow-window colour	hardware-parity.md	brush users with tablets; multi-monitor setups	11–22	hardware-parity
23	Accessibility audit with screen readers; canvas tools keyboard-reachable	LR-BEHAV-ACCESS 🟡	blind and low-vision users	10–20	ui-parity
24	Brush live preview and masking feel (#517, #518); Feather / Edge mask refinement (15.5)	issues	masking feels slower than Lightroom	8–12	ui-parity
25	File writes: PSD export, lossy DNG, Render to DNG; AVIF import	file-format-parity.md	interchange edge cases	21–37	file-format-parity
26	Performance at scale: 85k-photo library opens in 1.7–4.7 s; 100k grid test pending; colour NR at half resolution	ROADMAP log, gpu-pipeline.md	large-catalog users	15–30	target-app-parity
27	Windows / Linux runtime coverage: Windows installer UI unverified on Windows (#79); GPU path proven on Apple only	ROADMAP, issues	non-Mac users find bugs first	15–30	hardware-parity
28	Small Classic shortcuts and keys: rating [ ], flag cycling, filter-bar keys, F1 help, panel keys (Tab, F5–F8)	ui-parity	Classic muscle memory	4–8	ui-parity

Beta-blocking gaps (B) total ~230–430 h; with the stability and platform work they need around them, ~340–600 h to beta (incl. 40–80 h for the ~92 open core-path user issues) (see target-app-parity.md).

Gaps by kind

• Feature: 5, 8, 11, 12, 13, 15, 16, 18, 19
• UI / UX: 4, 23, 24, 28
• File format: 2, 6, 7, 10, 13, 20, 25 (raw ones in raw-parity.md)
• Hardware: 14, 17, 22, 27
• Localization: 21
• Quality / fidelity: 1, 3
• Stability and platforms: 9, 26, 27

Closed recently (kept for calibration)

• 2026-10-10: Nikon lossy-after-split NEF (#633), ORF 12.8 bpp (#651), HDR gain map / PQ AVIF / float TIFF export (#646), activity stack (#345), JPEG XL export (#247).
• 2026-10-09: HEIC in release builds (#609), Samsung uncompressed SRW (#459), contact-sheet PDF (#563), Ukrainian UI (#564), Sony ILCE-7CR profile.
• 2026-10-08: CR3 CRX lossless and C-RAW (#279), Fujifilm compressed RAF (#282), AI RAW denoise (#384), Lightroom catalog import (#218), German, Spanish, Russian UI.
• 2026-10-07: RW2 every format (#215), faces recognition in pure Rust (#174).
• 2026-10-05: compressed NEF (#86). The older history is in ROADMAP.md.

Revision history

Date	Change	Summary
2026-10-10	minor	RAW gaps re-measured model by model (raw-parity.md): CR3, compressed ORF and verification entries carry measured shares; HE NEF no longer a beta blocker (+1.1 points for 20–40 h); verification entry absorbs the cheap per-body fixes (#769, #702, A200 series)
2026-10-10	minor	Beta total raised to 340–600 h to include the ~92 open core-path user issues
2026-10-10	major	Created from the checklist's Top gaps (whose items 1–2 had been duplicated by a merge) and ROADMAP's Where we stand; re-ranked; added evidence, impact, hours and beta flags; added platform-CI, lens-database, HE NEF and localization gaps