On-device face detection finds the subject and scores focus there, not just the whole frame, so a sharp portrait on a plain wall stops reading soft. No face? It uses a center-weighted region instead.
Find the keepers, on device.
Lensgrade scores the photos you choose for sharpness, then goes further: subject focus, exposure clipping, and an EXIF shake check combine into one clear keeper-or-cull call. It grades delivered photos, not lenses, and everything runs on your device. No account, no uploads, no tracking, no in-app purchases.
A 256-level luminance histogram from the same pixels reports clipped highlights and shadows and a plain exposure verdict, so a keeper is judged sharp and well exposed.
Reads focal length and shutter speed from a photo's EXIF and applies the reciprocal rule, with a bundled crop-factor table, to tell shake-soft from focus-soft. Fully offline.
Batch a roll and Lensgrade groups frames into bursts by capture time and crowns the highest-scoring frame in each, turning a flat list into real triage.
Sort and filter your score log by sharpness, exposure, date, star, or keeper. Re-open saved batches as ranked groups, and export a batch as CSV to act on in a desktop workflow.
A 12-guide library, a 65-term glossary, a 42-format crop-factor table, and typical score ranges by scene, all bundled and readable with no network.