Sharpen Image

Drop your photos into the form and drag the "Strength" slider, or press "Auto sharpen". A curtain over the image shows the before and after.

How sharpening works

Edges in a photo are the places where brightness changes abruptly. Sharpening makes those transitions steeper: the light side of an edge gets slightly lighter and the dark side slightly darker, so the image looks crisper to the eye. Only brightness is amplified, not each color separately, so no colored halos appear around objects.

Strength and radius

• Strength — how much the edges are amplified. A sharp shot needs only 30–60%, a softer one needs more.
• Radius — the width of the edges in pixels. Below 1 picks out hair, eyelashes and fabric texture; 2–3 works on large contours.

"Auto sharpen" estimates how soft each photo is and picks both values on its own. The chosen values appear on the sliders.

What sharpening will not do

Sharpening emphasizes details that are already in the photo. A badly blurred or out-of-focus shot will look crisper, but the small details are gone for good. At high strength, grain shows up in flat areas and a light fringe appears around high-contrast edges — that is the sign to lower the strength.