Focus peaking

Press K to highlight sharp edges in green in Loupe, Compare or Develop.

Press it again, click the peaking button beside the magnifying glass, or use the View menu to hide the marks. The button is partly green while calculating and fully green when ready. Initial calculation takes about a second; repeating on the same pixels takes a few hundredths of a second.

Original pixels required. Proxies cannot provide peaking. Loupe waits for its paused-view decode or Load original. In Compare, resting fetches every pane’s original, and K fetches originals for every pane and marks each as it becomes available. Develop already has an original decode.

Changing photographs or arranging a new comparison clears the marks. In Develop, find-dust (⇧K) and focus peaking replace one another.

Reading the result. Peaking uses a fixed threshold across photographs, so poorly focused photographs show fewer marks. It reduces responses to sensor grain, although high ISO can still increase them slightly. Raising RAW Sharpening can produce more marks because measurement includes Detail adjustments.

The measurement follows original pixels through zoom, crop and straighten. Fit and 100% therefore show the same detected edges at different sizes. Marks are calculated for the current view and are not stored as a photograph score.