#1363 Expo bracketing in manual exposure mode at the minimum shutter speed: frames 1 and 2 are identical and all frames are tagged EV -2.0

[Anonymous]

App: Open Camera 1.56.2 (Google Play install, versionCode 96)
Device: Samsung Galaxy A37 (SM-A376U1), Android 16, build A376U1UES3AZE1, portrait, Camera2 API (the default on this phone)

Steps to reproduce

1. Fresh install (or clear app data); allow camera; OK on the intro dialog.
2. Popup menu (⋮) → Photo mode EXPO {} (bracketing settings left at defaults: 3 images, ±2 EV).
3. Exposure button → ISO 100.
4. Drag the shutter-speed slider fully left (1/29412 s on this phone).
5. Take one photo.

Expected: three frames spread around the chosen exposure (or a warning that the darker frame cannot go below the
minimum shutter speed).
Actual: frames 1 and 2 have the same exposure time (1/29412 s, i.e. 3.4e-05 s) and the same mean brightness; frame 3 is
1/7246 s (1.38e-04 s). EXIF ExposureBiasValue is -2.0 on all three frames.

How often: 5 of 5 runs, each from cleared app data: ev_bias [-2.0, -2.0, -2.0] every run; exposure times
[3.4e-05, 3.4e-05, 1.38e-04] s every run.
Control: the same install with default exposure (steps 3-4 skipped): 3 of 3 runs gave a proper spread, ev_bias
[-1.9, 0.0, 1.6] / [-1.8, 0.0, 1.6] / [-1.8, 0.0, 1.7], exposure times 1/480, 1/120, 1/30 s.
No crash or ANR in logcat.

Evidence: EXIF table per run (ExposureBiasValue, ExposureTime, ISO, mean luminance) read on the host from the
saved JPEGs. No photos or screen recording attached: the bench camera points at a room.

Limits of this test: one phone; one indoor scene; taps injected; we only reached the "all -2.0" symptom with a manual
shutter at the device minimum, so the reviewer's own trigger may differ (e.g. a very bright scene). Settings → Photo
settings → "Enable fast HDR/expo burst" was left at its default; we did not test with it disabled.

Related: #815 and #663 also report bracketing frames with the same exposure, but on default settings. Here the
default bracket is correct, and only the minimum manual shutter collapses frames 1 and 2.

Reported by LINC Innovations from an automated device-bench run. Happy to re-test a fix build.

https://lincinnovations.com