FITS Blaster — Beta Releases

Beta release notes

All betas since the last stable release, newest first.

1.24 beta 4: better metrics, clear frames no longer black, right-click menu — v1.24-beta.4

2026-11-05 · GitHub release ↗

Changed

Metrics are measured anew, closer to PixInsight. Scores and values from earlier versions can't be compared with the new ones.
SNR is the total light of each star divided by the sky noise, instead of the star's peak, so it shows exposure, transparency and sky brightness and no longer repeats the FWHM. The numbers are on a new scale (session medians of about 1,000–10,000).
The star count is close to PixInsight's (within about ±15 % on the test frames; before, from 7 × too few to 4.5 × too many). Noise on nebula and hot pixels no longer count.
Only real stars are measured: hot pixels on uncalibrated frames no longer pull FWHM and eccentricity around, and FWHM and eccentricity come from the bright stars.
Colour cameras: sky background and noise are measured per colour channel, so the sky colour no longer counts as noise.
Saturated stars are counted once each and left out of the measurements, on mono and colour cameras.
Large stars (long focal lengths, FWHM above about 8 px) are measured correctly: before, the FWHM of such frames came out far too low.
Frames without stars (fewer than 10: thick cloud, dew, a closed cap, a flat among the lights) get a score of 0 and are flagged by Auto-Flag with any check turned on.
Auto-Flag's starting values catch thin cloud and leave normal frames alone: SNR below 60 % of the session median, stars below 50 %, eccentricity above 0.65 (normal colour-camera frames measure about 0.5, so the old limit of 0.5 flagged a third to two thirds of a session). The red "trailing" badge uses 0.65 too. Scores are about 10–15 points higher for the same frame.
Filter groups with fewer than 3 frames skip the checks against the group median (Auto-Flag's relative mode, the focus and low-star badges); the Auto-Flag sheet says which groups. With an even number of frames the median is now the true median.

Added

Right-click a frame in the thumbnail bar for Show in Finder, Copy File Path, Flag/Deflag, Reject, Undo Reject and Remove from List. On a frame in the orange selection the menu acts on the whole selection.

Fixed

Clear mono frames no longer turn black after loading when the folder also has many bright frames (dusk, dawn, cloud) (GitHub issue #10).
The Open Folder panel slides down from the main window, so it can no longer end up behind it.

1.24 beta 3: folders read once, memory under control, zoom and pan keys — v1.24-beta.3

2026-10-31 · GitHub release ↗

Improved

Loading reads each file once: colour folders keep a small intermediate image from the first read, so their colour render no longer reads every file a second time, and mono folders get their shared stretch while the next folder loads. Over a network that is much faster: 355 colour frames (17.6 GB) from a 1 Gb/s share in 160 s instead of 287 s, 464 mono frames in 67–72 s instead of 108 s. From an SSD colour loads take about 30 % less time. The images are exactly the same.
The first frames appear right after the folder scan, without first checking every file (that took up to 13 s over a network).
Smoother sidebar and chart: a click on a thumbnail no longer redraws the whole sidebar, and the chart redraws at most four times a second while loading instead of for every frame.
Less memory while loading: each frame is read straight into its GPU buffer.
Sharp thumbnails on Retina screens, in the sidebar and in Quick Look.

Added

Memory for display images (Settings → Display → Memory): a slider from 10 to 90 % of the Mac's memory, 50 % by default. Above it, the frames you looked at least recently give up their display images and are drawn again from their file when you go back to them (blurry for a moment). At the default display size this rarely matters; at large sizes it keeps FITS Blaster from taking most of the Mac's memory.
Zoom and pan keys: = / + zoom in, - zoom out, 0 zoom to fit, 9 shows 1×; ⌥ + arrow keys pan a zoomed frame (a tap moves a quarter of the view, holding it scrolls). The zoom keys can be changed in Settings → Interface, and all of them are in the View menu.
Open several folders at once: ⌘-click them in the Open Folder panel; each gets its own sidebar section, and the two options apply to all of them.

Changed

⌘-click selects or deselects a single frame, as in Finder; flagging is the flag key or the (De)flag button only.
"Max thumbnail size" is the width the sidebar shows, in points (80–400, default 180), and the sidebar follows it. Changing only the thumbnail size no longer reloads every frame.
Files FITS Blaster doesn't load (floating-point FITS, stacks with colour planes) are left out during the load and named in one message.
Two folders with the same name (two nights' LIGHT), opened or dragged in together, get their parent folder in the section name, so they stay apart with their own stretch.

Fixed

Star counts are the same on every run, also on very dense or noisy frames (more than 50,000 candidates): before, the count could differ by a few stars between runs. On such frames the count is now the complete one (in the test data one frame: 3389 stars on every run instead of 3371–3373).
The Settings window follows the theme setting; it could be light beside a dark main window.
Colour images follow a new display size; with Colour on they kept the old size.
A failed GPU pass is no longer shown as a black image or read as "no stars": the app falls back to the CPU.

Under the hood

The command line measures without making images when it doesn't render, and the test baselines are stricter. Measurements are unchanged apart from the star-count fix above.

1.24 beta 2: faster network folders, smoother browsing, safer loading — v1.24-beta.2

2026-10-26 · GitHub release ↗

Improved

Opening folders over the network is much faster: listing the folder and checking the files went from over a minute to about 15 seconds for 1,147 files on a 1 Gb/s share. While FITS Blaster prepares a load you now see "Scanning…" and "Checking files" with a progress bar instead of an empty window.
Holding an arrow key is smooth again in large sessions: the sidebar keeps up without stutter (5 short hitches in 5 seconds instead of 39–57 in a 355-frame session). Scrolling a zoomed frame redraws less too.
Much less memory with many folders or filters: a session of 464 mono frames in 8 folders × 3 filters now peaks at 1 GB instead of 4.4 GB while loading.
Open Folder: "Include files from subfolders" and "Include REJECTED folder" are back in the folder panel itself, and scanning a large folder no longer freezes the window. Dropped folders are scanned in the background too.
Export: the header columns follow the order you chose in Settings → Export. Text that a spreadsheet could read as a formula is protected, and a failed export now shows an error.

Fixed

A second folder during a load (opened or dropped) now waits for the first one. Before, the progress bars disappeared and Cancel greyed out while the second folder was still loading.
Reset during a load stops the load; it can no longer add frames to the emptied session.
Colour toggled during a load now ends correctly: turned on, every frame ends in colour, also the frames that weren't loaded yet; turned off, every frame ends in grey. Toggling quickly ends on the last setting.
Cancel also stops a colour re-render, and no longer measures the remaining frames one by one.
Several folders dropped at once each get their own section in the sidebar, in the order you dropped them.
The info bar above the chart no longer disappears when you select a frame that is still loading.

Changed

A colour toggle can be cancelled (Cancel is active while it runs), and a display-size change made during a load runs after the load.
Files with Finder's "hidden" flag are no longer skipped when a folder is scanned (files whose name starts with a dot still are).

Under the hood

The loading pipeline was rebuilt so batches run one at a time, and the app now compiles in Swift 6 language mode, which turns data races the compiler can detect into errors. Measurements and image rendering are unchanged.

1.24 beta 1: keyboard, REJECTED folder and chart fixes — v1.24-beta.1

2026-10-24 · GitHub release ↗

Fixed

Keyboard shortcuts only act in the main window. Pressing a shortcut key in Settings, a sheet or a popover no longer flags, removes or rejects frames in the main window. Recording a shortcut on a key that's already in use works again.
Undoing a rejection never deletes hidden files. The REJECTED folder is only removed when nothing but Finder's .DS_Store is left in it.
A frame rejected in this session no longer loads twice when you reopen the folder with its REJECTED folder.
Session chart while loading: dots appear at their final place, and clicking one selects the right frame.
Removing frames no longer leaves them in the reject selection.

Improved

Text size (Settings → Interface → Appearance) now also applies to the chart's axis and hover labels and to the flag and flip badges on thumbnails.
VoiceOver announces the image as a button that sets or clears the zoom anchor.
The explanation under Settings → Display → Colour Images is corrected.

Under the hood

About 500 lines of unused code removed and many outdated comments corrected, in preparation for the next 1.24 steps. Measurements and image rendering are unchanged.