Check image sharpness: what the score means
| Word | Acutance | What it usually means |
|---|---|---|
| Crisp | 0.62 and over | Edges as steep as the lens and sensor deliver |
| Acceptable | 0.40–0.62 | Fine at screen size; soft at 100 % on large prints |
| Soft | 0.22–0.40 | Visibly soft at 100 %; sharpening helps |
| Blurry | under 0.22 | Out of focus or shaken; see the unblur triage |
A sharpness score compares pictures of the same scene; it cannot rank a portrait against a landscape.
From the ranking to the sharpener
After a burst is ranked, Open the sharpest in the sharpener hands that frame to the console on this page, in memory. To decide what to do with a soft frame, the unblur triage names the kind of blur and runs the pass that suits it; a frame that is only a little soft goes to the sharpener.
Questions about checking sharpness
How is sharpness measured?
As acutance: the mean steepness of the strongest two per cent of edges in the busiest part of the frame, measured at the file's own resolution. It is shown as a number and a word — crisp, acceptable, soft or blurry — never as a percentage pretending to be absolute. Noise is measured alongside it, because a noisy file can look crisp to a gradient and still be soft.
Can I compare two different photos?
Only pictures of the same scene. A sharpness score compares edge steepness, and a portrait against a soft background has fewer strong edges than a brick wall however well each was focused. For a burst, every frame is measured in the same place, so the ranking is fair; across different subjects it is not, and the page says so.
Why is my photo marked soft when it looks fine on my phone?
Because a phone screen shows it reduced. A 12-megapixel photo seen at phone size is downscaled about six times, which hides softness that is plain at one image pixel per screen pixel. The score is taken at full resolution; the focus map shows where in the frame the softness sits.
What does the focus map show?
The frame divided into a grid, each cell scored by its own strongest edges and labelled C, A, S or B relative to the sharpest part of the same picture, with a pattern as well as a colour. It shows where focus actually landed — on the eyes or the ear, the sign or the wall behind it.
Does anything leave my device?
No. The frames are decoded and measured in this tab. The report is text you can copy; no pixels are written out.
