Quick answer
Point AstroLoupe at the folder your capture software writes to, and it does the rest - no import, no library to manage. Most questions below are about file formats, performance, or where AstroLoupe keeps its data. If you're stuck on something not covered here, just email me - I read every message myself.
AstroLoupe won't open one of my files
- Check the format is one AstroLoupe supports: FITS (including RGB cubes and 32-bit float), XISF, TIFF, PNG, and camera RAW (CR2/CR3, NEF, ARW, DNG).
- AstroLoupe is sandboxed, so it can only read files inside a folder you've explicitly opened - if a file lives outside that folder (a different drive, a moved file), reopen the correct top-level folder rather than pointing at the file directly.
- A handful of very old or non-standard FITS files use header conventions AstroLoupe doesn't recognise. If a file fails to open, send it to me (see Contact below) and I'll take a look.
Colours look wrong on a one-shot-colour camera
AstroLoupe debayers automatically based on the BAYERPAT keyword in the file's header. If that keyword is missing or your capture software writes it differently than expected, the frame may render as mono or with an unexpected colour cast. Check what your capture software actually wrote to the header - if BAYERPAT is absent or non-standard, that's the cause.
Plate solving isn't finding a match
- Solving works fastest when the header already has an approximate focal length and pixel size - if those are missing or wrong, try a full blind solve instead, which searches without them but takes longer.
- Very wide or very narrow fields, or frames with few detectable stars (short subs, heavy light pollution, narrowband), can be genuinely harder to solve. Try a longer/brighter test frame from the same session first.
- Solving is matched against a Gaia DR3-based catalogue bundled with the app, so it needs no internet connection - if it's failing, it's not a connectivity issue.
Where does AstroLoupe store its data?
AstroLoupe never modifies your image files. It keeps a small local index (frame metadata such as object name, equipment and exposure details, read from your files' headers) inside its sandbox container:
~/Library/Containers/com.cambridgeaiworks.astroloupe/
Deleting the app removes this too. Nothing is ever sent anywhere - see the privacy policy for the full picture.
Performance is slower than I expected
AstroLoupe renders on the GPU and fans batch analysis (grading, tilt, aberration) across every CPU core, so it should feel fast even on large sessions. If a particular folder feels sluggish, it's usually either an unusually large number of very high-resolution subs being graded at once, or files being read over a slow network drive rather than local storage - try copying a session locally first if you're working from a NAS.
Purchases and refunds
AstroLoupe is sold through the Mac App Store, so purchases, receipts and refunds are all handled by Apple - I don't have access to your payment details or purchase history. Start a refund request at reportaproblem.apple.com.
Feature requests
AstroLoupe is actively developed, and most of what's in it started as something an imager asked for. If there's a measurement, format or workflow step you're missing, tell me - I read every suggestion, even if I can't promise it'll ship.
Contact
AstroLoupe is made by Cambridge AI Works Ltd. For anything not covered above - bugs, crashes, a file that won't open, or just a question - email [email protected]. Including the problem file (or a short description of your session/equipment) usually gets to an answer faster.