Appendix E — Release notes

Generated from the annotated v* tags (docs/make-releases.sh).

v0.97 — 2026-09-04

v0.97 — the PSF study comes home: Measure PSF, calibrated deconvolution, Gaia DR3, and a fast cache

Highlights:

  • Tools ▸ Measure PSF — the study’s stellar instrument, native: elliptical Moffat fits over the frame’s isolated stars, per channel the major/minor FWHM (px, and arcsec under a plate solution), eccentricity with its position angle, the Moffat beta, and a 3×4 field map that separates one-axis drift (uniform PA) from optics (PA turning toward the corners). Annotate stars drops rotated ellipses with optional FWHM/eccentricity labels; results are cached per image; a single monotone progress bar spans the job. Scripts: measure_psf, psfannotate [mode].
  • Tools ▸ Deconvolve to Target PSF — the appendix’s calibrated method in one linear pass: measured Moffat kernel in, declared circular-Gaussian target out, the MCS single-filter transform (the partial kernel is never formed). Its honesty ships with it: a contract-first λ ladder keeps the strongest regularization whose delivered FWHM honours the declaration within 5% per channel; the result’s stars are re-fitted and the delivered figure written into the header; saturated cores are protected. Validated on the M16 master: in-app measurement reproduces the certified table, and a 1.90″ declaration delivers 1.96–1.97″. Scripts: deconv <fwhm_px> [lambda].
  • Noise prior inside the deconvolution — Regularization by Denoising (starlet à-trous soft threshold, per-scale MAD) as an option of the same dialog: the same inversion with the denoiser inside, warm-started from MCS, the prior weight obeying the same contract-first ladder. At equal delivered PSF the background comes in 3.6–5.5× quieter than the pure filter, and a ctest holds the bound. Pure MCS stays the default. Scripts: deconv <fwhm> red [iters] [weight].
  • No square artefacts around stars — three field reports at 1.7–1.8″ contracts, traced by bisection to their real sources and all fixed: separable (square) core protection is now a round radial stamp; the starlet prior is star-neutral, thresholds only the three finest scales, and stays out of round brightness-tiered zones around bright stars; and the root cause, the Moffat kernel’s hard truncation at its canvas edge printing a dark frame around every saturated core, is gone: the kernel lives on a wide canvas with a radial cosine taper to a true zero. The non-FFT paths are parallelized: the full 1.7″ RED pipeline on a 61-megapixel master takes 72 s.
  • Gaia DR3, in-app — the app’s first use of the network (ESA TAP; only sky coordinates leave the machine; soft failure offline). Right click ▸ Identify Star in Gaia DR3 refines the click to the fitted star centre and reports the NEAREST source (source_id, G, BP−RP, parallax and distance, separation), with a violet annotation at the CATALOGUE position so a plate-solution offset is visible. Right click ▸ Gaia DR3 Field Overlay draws the brightest sources of the visible region at their catalogue positions, one undo step. Positions are proper-motion-propagated from 2016.0 to DATE-OBS; dense galactic-plane fields are served by a bright-first magnitude ladder. Scripts: gaiastar x y, gaiaoverlay [count] [labelN].
  • Auto STF (PixInsight) on P — a NEW stretch option, Juan Conejero’s STFAutoStretch verbatim with no floors (clip at median − 2.8·1.4826·MAD, midtone by the MTF parameter identity), for the raw narrowband master that rendered near-black and green under the classic Auto STF because one saturated star pinned the window. The existing Auto STF options are byte-identical to before. Script: autostf pi. (P leaves the Info panel, which keeps F4.)
  • Decoded-image cache and neighbour prefetch — an LRU of the post-debayer decode plus statistics (Preferences ▸ Image cache, default 4096 MB): switching back to a 495 MB master costs 0.3 s instead of 13. Every hit re-checks the file’s mtime and size, so an external overwrite is never served from memory. The next and previous rows prefetch in the background, so a first-pass blink is instant.
  • Neutralize Background from Sky Patch — the v0.96 tool restated after three field rounds: only the black point moves (midtone and white keep their absolute positions), and the three channels are equalized to a common dark grey rather than black, so faint nebulosity stays visible. Apply it late in a session, once the stretch is settled.
  • Appendix: the study continues — the Hubble-overlap audit grows to eight renders (BlurXTerminator ML4/ML5 on both stacks, the two calibrated products), with the principle that stellar analysis is measurement only on raw and calibrated data; a ninth row tries proper coaddition (Zackay & Ofek 2017) on all 201 registered subs, whose referee turned out to need auditing itself: star contamination was driving the fidelity metric, so metric v2 removes stars symmetrically with a null test on half stacks. Verdict, recorded honestly: proper coaddition buys resolution (Hα 2.53″ vs 2.93″ for a plain mean of the same frames), not fidelity. Instruments under tools/psf_study/: ml5_audit, patch_extract, proper_coadd, patch_audit, sxt_subs, and the palette-montage pipeline.
  • Demo package — demo/STORYBOARD.md plans the presentation video in two cuts, each scene a .nsc script validated against real data.

Also: the TRANSPORT chapter states the stretch fit’s optimization as it now is; QTimeZone::utc() for pre-6.5 Qt on the Linux runner.

v0.96 — 2026-08-31

v0.96 — the histogram shows the result: live output distribution, sky-patch neutral black, identity restarts

Highlights:

  • The histogram shows the OUTPUT distribution — the filled shape is now the result of the current stretch (the input stays as a faint dotted outline; the transfer curve overlays both), computed by pushing the data histogram through the curve — no image pass, so it tracks every drag tick live. And because that feedback is free, the image render is deferred until the control is released: a 60-megapixel master drags fluidly and renders once, from the final position.
  • Neutral Black from Sky Patch — neutralising the background is a per-filter-pedestal problem, and the estimate is the risky part: so you point. Drag a small rectangle over truly empty sky and each channel’s black point becomes that patch’s median in that channel — exactly three simultaneous B-drags (midtone as a ratio, white untouched), non-destructive, one undo step. It lives in the B/W windows, so it survives into Log/Asinh and GHS. Scripts: blackpatch x y w h.
  • Identity restarts for the composed stretch — set up Linear, then neutralize before shaping: M → identity (Log/Asinh) resets every channel’s midtone to the window midpoint; Shape → identity (GHS) sets D to zero with b/SP/LP/HP keeping their anchors. The manual now states who is per-channel (Linear: B/M/W; Log/Asinh: window and midtone; GHS: one shared shape anchored through each channel’s own window — and the midtone is NOT part of the GHS composition).
  • Lossless colour transport can turn a palette — the “as stretch” fit’s colour stage is now a fitted 3×3 mixer (closed-form weighted least squares), alternated with the per-channel curves so the two stages solve a joint problem. Starless pairs — whose transport is mostly a cross-channel rotation — now match instead of washing out grey. The display block gains schema 2 (optional adjust.mix, written only when present; reference renderer and conformance case updated), and both lossless options are on by default.
  • Reset Orientation is forceful — rotation state lives in three places (data histories, calibrated-link transforms, view navigation) and a calibrated Match legitimately puts rotation into the viewport; Reset Orientation now vacates all of it, for every image and every view, redisplaying everything as freshly read. No confirmation: the result is the well-defined just-opened state.
  • The visible region is the quad, not its bounding box — with a rotated navigation, Export Zoomed Region is now WYSIWYG (resampled through the view transform; scripts: export region <path>), and data crops and the colour-transport relevance masks use the largest rectangle INSIDE what is shown — off-screen sky no longer steers a transport (the “khaki wash” field report).
  • Zoom to Width (W) — fill the viewport width; a portrait image fills the screen and scrolls vertically, keeping your position.
  • Appendix: Measuring a telescope against Hubble — the PSF study (star-free kernels against HST ground truth, the stellar/nebulosity asymmetry of neural deconvolution, and a full-frame calibrated deconvolution with a stated, audited model) joins the book as an appendix, with its four instruments under tools/psf_study/.

Also: the ADJUST header says what it does (all channels — the selector scopes the histogram view, not the sliders), and the colour-fit stage’s hue search domain is fixed (it was capped at one degree; a starless palette rotation could never be expressed).

v0.95 — 2026-08-19

v0.95 — comparison as an instrument: Match, Values in All Views, the open display format

Highlights:

  • Match views (M) — calibrated linking by computation or by two clicks instead of by eye. With two plate-solved views, M computes the correspondence from the WCS (pixel→sky→pixel over the overlap, affine-fitted; the status bar reports the residual) — no picks at all. Otherwise: rough-align, M, click a star in one view and the same star in the other — one pair snaps the translation exactly; Shift+M and a second star solve scale + rotation + translation in closed form. Verified against ground truth to 0.001 px (features) and 0.02 px (WCS).
  • Values in All Views (V) — hovering the active view shows the coordinates and pixel value(s) under the pointer in EVERY cell, each read from its own data at the corresponding pixel (through the calibration for matched views), with a crosshair in each cell at the measured pixel. The link transforms made visible: hover a star and see whether the other view’s crosshair lands on it.
  • The display block is an open, reproducible format — Save Annotations & Display stores the full appearance (transfer function, per-channel windowing, GHS, colormap, adjustments) in the sidecar under a versioned display key. A written specification (Colour Transport chapter §6) maps every field to its equation, and a standalone NumPy reference renderer (tools/render_sidecar.py) reproduces NebulaScope’s rendering — verified in CI to a few float32 ULPs per pixel on macOS, Linux and Windows. A stretch becomes explainable; a non-destructive transport fit becomes a file you can hand to a collaborator.
  • Native save panels on macOS — Export View As… and Save Data As… are real NSSavePanels with the format / depth / compression / quality controls as a native accessory row (sidebar favourites, iCloud, folder behaviours). Clicking any image still adopts its base name; the saved extension always follows the chosen format.

Fixes: in the docked layout, clicking between split cells no longer shifts the grid (the hidden Info tab’s statistics table was resizing the shared dock area); a non-destructive transport fit saved in a sidecar now reloads exactly (the sidecar carried only the adjustment layer, not the stretch); shortcuts.ini records each entry’s default, so renamed default keys follow the release while user customisations survive.

Illustrated in the manual by the Eastern Veil, two nights: a friend’s 5 h on a Vixen 102/900 matched to ~1 h on a TS 80/380, colours transported non-destructively — what remains different is signal, not processing.

v0.94 — 2026-08-14

v0.94 — selection-aware culling, instant batch close, metadata-less CFA, Stellarium

Highlights:

  • Selection-aware image list — the culling keep-checks understand multi-selection: B group-toggles the highlighted rows (checks all; unchecks only when all are already checked), clicking a checkbox inside a multi-row selection retags the whole selection, and C closes every highlighted image. The context-menu entry is now Close & Remove from List, and it means it: decoded pixels, per-view copies, and all per-image state are freed on close. In-app results (Combine, transport, crop) carry the keep-check too.
  • Instant batch close — closing hundreds of blinked frames used to freeze the app for tens of seconds: each removed row triggered a full decode of its neighbour. Row removals now run signal-blocked with a single display fix-up, so clearing a 400-sub session is instantaneous.
  • Annotation-safe closing — when closed images carry unsaved annotation edits, one prompt covers the whole batch: Save Annotations writes every affected image’s default sidecar, Ignore and Close discards, Cancel aborts untouched.
  • Metadata-less CFA (mosaic sniffer) — planetary/solar capture tools can dump raw Bayer mosaics into plain grayscale PNG/TIFF with no pattern keyword anywhere. NebulaScope now detects the mosaic statistically on open and names the two candidate patterns in the status bar; Image ▸ Debayer ▸ Apply Choice to All in List (script: debayer bggr rcd all) stamps a forced pattern onto a whole capture stream. Born from — and illustrated in the manual by — the total solar eclipse of August 12, 2026.
  • Point Stellarium Here — the sky context menu can point a running Stellarium (Remote Control plugin) at the clicked J2000 coordinates, field of view matched: where Aladin/SIMBAD answer “what is this”, Stellarium answers “where is it in tonight’s sky”.
  • Clean canvas — H now also hides the active-cell border and link buttons; with fullscreen (⌥F) the display is pure image, e.g. to preview a wallpaper.

Also: HISTORY.md, a development chronicle of how this program came to be; design notes on the removal cascade in DECISIONS; French translations for everything above.

v0.93 — 2026-08-06

v0.93 — PixInsight display interop, stretch history, DS9 palettes

Highlights:

  • PixInsight display interop — a PI-saved XISF now opens LOOKING as PI showed it, with far-out STF white points rebased onto the data range in closed form (histogram controls stay fully usable, SPCC channel balance preserved exactly; derivation in the book’s new Mobius-rebase appendix): the embedded display function (STF) applies on first view, embedded ICC profiles are honoured, and on macOS the window is colour-managed for wide-gamut (P3) panels. The transfer LUT adapts its resolution to the occupied window and the histogram’s curve overlay is evaluated exactly — imported stretches with far-out white points render smoothly.
  • Stretch undo history — every stretch/adjustment gesture is one undo step (drags coalesce): ⌘Z walks back to the as-loaded state, through Auto STFs, pastes, transport fits. Reload Original (⌘⇧R) re-decodes from disk and re-runs the first-view rules, itself undoable.
  • DS9 classic palettes — a, b, bb, he, cool, rainbow, standard, and the stepped i8, aips0, sls, reproduced from SAOImage DS9’s reference control points (renditions match DS9 exactly); compose with the invert/split modifiers. Requested by a user.
  • Save ergonomics — an in-memory result’s list entry takes the saved file’s name on every save path (Save Data As, Save Stretched As, script save); clicking any image in a save dialog adopts its base name, the extension following the chosen format.
  • Build provenance — the About headline and –version carry the exact git build id, so test binaries identify their commit.

An imported UNLINKED display function (the channel-equalizing STF that visually cancels an SPCC calibration) is flagged in the status bar with the remedy: Shift+U preserves calibrated colour. The import pipeline is regression-tested end to end via synthetic XISF fixtures and the new assert stretch script assertion.

Fixes: linked histogram drags are rigid (per-channel clamps no longer ratchet the channels’ offsets apart on repeated drags); the panel-resize cursor no longer sticks over overlay panel contents; the script cmap command actually applies the selected map.

v0.92 — 2026-08-04

v0.92 — list & session ergonomics, inline export options, display sampling

Highlights:

  • Large-list workflows — drag a list row onto any view cell to show it there; the list holds each image once (re-opening selects the existing row); batch opens fill the empty cells in the order given; Clear List & Close All (⌥C) sweeps the session in one stroke. Together with Apply to All and blink culling, per-filter inspection of a full night’s acquisitions is now a tight loop.
  • Inline save options — pixel depth (PNG/TIFF), quality (JPEG, and now WebP), and XISF compression are options INSIDE the save dialogs, enabled by the selected format — no follow-up prompts.
  • Display sampling — bilinear when zoomed out (kills the moiré that nearest-neighbour subsampling beats out of CMOS fixed-pattern noise), crisp nearest-neighbour at 1:1 and beyond.
  • Window & dialogs — ⌥F is the green button on a key (native full screen on macOS; maximize elsewhere); every file dialog starts in the current image’s directory.
  • Fixes — Zoom to Fit/1:1 acted on the wrong cell in split views (stale receiver); overlay panels no longer hide behind newly created cells after a split; Finder open events carry status-bar feedback and Console logging; proper French plural forms for counts.
  • Manual — §12 gains a real-data showcase: NGC 7331 with SN 2025rbs, a C11 beside a 180mm camera lens in linked views. Release notes now live in the annotated tag, rendered identically on the release page, in the manual appendix, and in both PDFs.

v0.91 — 2026-08-01

v0.91 — French localization, blink culling, crop tool, transport stretch fit

Highlights:

  • Français — the full UI is localized (system-language default, Preferences ▸ Language override, --lang CLI flag), alongside a French user manual and colour-transport chapter: on the manual site, and as a second PDF on every release. The .nsc script language and CLI output stay English as a stable, locale-independent API.
  • Colour transport, stage two — the non-destructive stretch fit (matches the transported look with zero data loss — cannot posterize, never amplifies noise) gains intensity weighting and an optional cross-channel colour-adjust stage for hue-rotation targets. Undoable; derivations in the new Colour Transport chapter.
  • Blink culling — keep-checks on every list row (toggle with B while blinking), then sort / move / remove checked frames; scriptable via tag/tagsort/tagmove/tagremove.
  • Crop to Visible Region (Shift+C) — full-bit-depth crop into a new list entry; the astrometric solution survives exactly (CRPIX rebase), annotations and stretch follow.
  • Keyboard zoom — > / < (10%) and . / , (3%), configurable; arrow keys reserved for panning.
  • Manual online — the documentation book is published at https://hugues-talbot.github.io/nebulascope/ (English) and /fr/ (français), rebuilt on every docs change.

Fixes: large TIFF re-open (Qt decode allocation limit), XISF→FITS metadata preservation (typed keyword values; standard cards synthesized from PixInsight properties), Save Annotations enabled for orientation-only state.

v0.90 — 2026-07-30

v0.90: OSC debayering (RCD validated against Siril, undoable), auto-reload interop, fast batch opens, shared STF, stretch-function shortcuts

v0.89 — 2026-07-28

v0.89: script-command CLI reference (–run list / –help ), Quarto documentation book, PDF attached to releases

v0.88 — 2026-07-28

v0.88: scripted documentation complete, dialog automation, transport CLI, macOS open fix

v0.87 — 2026-07-28

v0.87: testing + docs consolidation — 7 CTest suites on 3 platforms, PI interop fixtures, script-driven screenshots, zstd/Finder-open/split fixes

v0.86 — 2026-07-26

v0.86: XISF block compression re-enabled, save-time codec choice (Zstd/Zlib/Uncompressed); CI: Qt imageformats + Windows test DLL paths

v0.85 — 2026-07-24

Unit test with a cheap command language.

v0.84 — 2026-07-24

New features described in the manual, more extensive testing.

v0.83 — 2026-07-24

Rotation adding border persistent bug removed

v0.82 — 2026-07-24

Optimal transport colour match. Amazing feature.

v0.81 — 2026-07-23

General improvements to the user interface

v0.80 — 2026-07-23

This version sets up a workable distribution system on Github

v0.73 — 2026-07-23

This version is deployed on github

v0.72 — 2026-07-23

This version compiles on Windows, Linux and Macos

v0.71 — 2026-07-22

Version with side panels

v0.70 — 2026-07-21

New version with linked view. Totally cool

v0.52 — 2026-07-20

Now we have annotations, pretty solid and consistent.

v0.6 — 2026-07-21

This version now reads and displays sextractor catalogs as annotations.

v0.5 — 2026-07-19

Smooth display pipeline: dithered, interpolated rendering

v0.0 — 2026-06-26

v0.0: project inception — FITS/XISF inspector skeleton with histogram stretch