* Adding first version of sqm measurement

* Added UI screen, some refactoring for jupyter debugging

* Fix crash on no solution

* No shared_state crash

* Protect against various crash situations

* Swapping centroid y/x

* Added bortle classes, radius=3

* Now try radius=2

* Raw output for camera in shared state

* Introducing bias image

* feeding linear image through pipeline

* Delete and ignore comets file, sqm fixes

* Fix bias image bug

* Missing bias image arguments

* Another raw_image mention removed

* Add debugging output

* Merged main with the location changes

* Final version of sqm ui

- still has the bias frames, will be removed next commit
- added bortle descriptions in the ui

* Add unit test

* Removed bias, added performance code

* speed up per-star calculations

* Less info logging, translations, fix nox error

* fix messages

* Updated other languages with translation

* Perform SQM every 5 secs, prettify the SQM ui

* Fix linting error

* Some raw and pedestal changes

* Add default dark frames

* Better noise floor

* fix exposure

* leave exposure

* Noise floor fixes

* processed vs raw

* marking menu for pro sqm

* add sqm calibration

* Immediately reload measurements

* improve sweeps and camera type, maybe camera type should be reverted

* Raw pipeline

* Cleanup

* Cleanup after partial PR review

* Refactoring camera handling and sqm calibration

* Do sqm calibration captures in manual mode

* small AE and sqm fixes

* Solve stuck

* show background during sqm

* Fix name error

* another fix

* resize

* Stretch image

* Fix SQM sweep capture for production readiness

- PNG Processing: Changed sweep to save 8-bit processed PNGs using capture() method
- GPS Time Integration: Sweep now uses GPS datetime from shared_state
- Altitude Calculation: Added automatic altitude calculation from RA/Dec
- Metadata Saving: Implemented comprehensive metadata saving with save_sweep_metadata.py
- Progress Bar Fix: Updates progress for every image (not every 10th)
- Background Clamping: Modified SQM calculator to clamp negative backgrounds to 1 ADU
- Type Hints: Added proper Optional[] type hints for mypy compliance

* Fix cedar-detect shared memory crashes and variable shadowing

Cedar-detect shared memory fix:
- Fixed intermittent FileNotFoundError when cedar-detect has shared memory issues
- Client now gracefully handles missing/stale shared memory
- Automatically falls back to non-shmem mode instead of crashing
- Updated tetra3 submodule with robust error handling

Variable shadowing fix:
- Fixed linter error where 'time' variable shadowed 'time' module import
- Renamed to 'obs_time' for clarity in altitude calculation

* Add real-time progress UI for exposure sweep
* fix crash on sweep

* time based progress of sweep

* Fix sweep

* Use GPS time

* Fix json writing

* fix altitude calc

* Improve exposure sweep

* Better counting and solver crah

* more solver indenting

* Improve sweep UI

* Handle daytime calibration

* Add correction ui and help

* Add sqm debugging sweeps

* Adding SNR AE

* Add rotating constellation/SQM display to title bar

Adds a rotating info display that alternates between constellation name
and SQM value every 3 seconds with a smooth cross-fade animation.

* Add exposure time display to SQM view

Shows current camera exposure time (e.g., "400ms" or "0.40s") in the
top right of the SQM view for diagnostic purposes.

Cherry-picked from test-upstream branch.

* Simplify Bortle class display on SQM view

- Remove redundant title text display
- Add guard for missing details
- Use base font for consistency

* Remove dual pipeline references from SQM code

- Remove unused value_raw from SQMState
- Rename update_sqm_single_pipeline to update_sqm
- Rename sqm_raw to sqm_uncorrected (more accurate name)
- Remove raw SQM display from UI
- Clean up outdated comments

* Refactor rotating display into compact helper class

Extract RotatingInfoDisplay class to encapsulate state and animation logic.
Reduces code by ~100 lines while preserving cross-fade animation behavior.

* Derive SNR controller thresholds from camera profile

- Add from_camera_profile() factory method to ExposureSNRController
- Calculate min/target/max background from bit_depth and bias_offset
- Target background just above min (no benefit to higher values)
- Remove arbitrary 400ms min_exposure floor (now 10ms)
- Remove 5-second rate limiting (averaging handled in SQM code)

* Update tetra3 submodule to match main

* Fix KeyError on T_solve when solver fails

Check if T_solve exists in solved dict before accessing it.
Previously checked wrong dict (solution vs solved) or didn't check at all.

* Fix update_sqm parameter name mismatch after merge

* Fix KeyError when deleting optional solution fields

* Fix camera type detection for SNR controller

* Remove duplicate solver code block from bad merge

* Add saturation detection to SNR controller

* Exclude saturated stars from SQM instead of reducing exposure

Move saturation handling from auto-exposure to SQM calculation:
- SQM: detect saturated stars (max aperture pixel >= 250) and exclude
  from mzero calculation by setting flux to -1
- Auto-exposure: remove saturation detection, just target background level

This allows longer exposures for better background SNR while ignoring
bright saturated stars that would corrupt the photometric calibration.

* Fix TypeError in SQM correction UI

colors.get() only takes intensity, not red=True keyword argument.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* Fix SQM correction: value_raw attribute does not exist

SQM state only has value, source, last_update - not value_raw.
Store source in metadata instead.

* Target minimum background for shorter exposures

Change target_background from min*1.25 to min+2 for more linear
camera response and less saturation risk.

* Use adaptive noise floor for SNR auto-exposure

- Add noise_floor to shared state (solver writes, camera reads)
- SNR controller uses adaptive noise floor + 2 as min_background
- Falls back to static camera profile if noise floor not yet available

* UX: Show 'Saving...' during correction save, target exact noise floor

- Show 'Saving...' message immediately before creating zip
- Remove +2 margin from noise floor - target exact value for shortest exposure

* Add noise_floor and imu_delta to correction metadata

* Add full SQM calculation details to shared state and correction metadata

Includes: mzero, mzero_std, background, pedestal, extinction, star counts,
saturation info, etc. - everything needed for calibration validation.
* Show star count in SQM view
* Move star count to top line in SQM view

* Add bracketed exposures to correction package

Captures 3 exposures: base, +1 stop, -1 stop (or base, -1, -2 if at max).
Shows progress for each bracket. Re-enables auto-exposure when done.

* Reduce exposure sweep from 100 to 20 images

Faster sweep (~1 min vs ~4 min) while still sampling exposure space.
Launch from SQM view → hold square → DEBUG.

* Use flux-weighted mean for mzero calculation

Brighter stars have higher SNR so their mzero estimates are more reliable.
Weight each star's contribution by its flux.

* Restore +2 margin above noise floor

Without margin, background_corrected ≈ 0 when at noise floor,
causing log10(~0) = very negative, making SQM too high.

* Fix SQM calculation: use bias_offset only as pedestal, disable extinction

Two fixes for SQM being ~0.4 mag too high:

1. Use only bias_offset (6.0 ADU) as pedestal instead of full noise_floor
   (7.46 ADU). Read noise and dark current are random fluctuations, not
   systematic offsets that should be subtracted.

2. Disable atmospheric extinction correction. When comparing to ground-based
   SQM meters, both measurements are through the same atmosphere, so no
   correction is needed.

* Re-enable extinction correction with 0.1 mag/airmass coefficient

* Add dual extinction correction: fixed 0.1 for meter match, altitude-based for science

- Main SQM value uses fixed 0.1 mag extinction (matches consumer SQM meters)

* Use ASTAP extinction convention: 0.28*(airmass-1), no fixed baseline

* better default for camera

* small corrections to sqm calculation and athmospheric correcitons

* Simplify SQM API, fix read noise calculation, add Cedar fallback

* Set SNR as default for testing

* Fix PID auto-exposure crash and improve sweep recovery

- Fix PID integral crash: Reset integral when error changes sign
  (prevents -487,500µs crash when going from too many → too few stars)
- Start sweep at 400ms instead of 25ms for faster recovery
- Add sleep mode logging to diagnose camera blocking issues
- Revert default to PID (SNR exposures too long on clear nights)

* Update tests for sweep starting at 400ms

Tests now reflect the new sweep pattern that starts at 400ms
instead of 25ms for faster recovery.