Sharpen an Image Without Drawing a Halo Around It

A halo is the signature of a mask that went too far

An unsharp mask finds a difference between the picture and a blurred copy of itself, then adds that difference back. On a hairline against a sky the difference is a thin dark ridge and a thin light ridge. Turn the amount up and the ridge becomes a white outline you can see at arm’s length. That outline is not detail the camera captured. It is the filter announcing itself. If a file already has that outline, do not send it through unblur. Unblur will treat the halo as an edge and make it more confident.

Re-export the photograph from the editor with the sharpening amount at zero, or as close to the camera original as you still have. A JPEG that was sharpened, saved, sharpened, and saved again has two generations of halos, and the second one is baked into the blocks. The tool cannot subtract a filter that has been quantized. The slider will show you a louder version of the same mistake.

Screenshots and logos are the other failure. Their edges are already one pixel wide and perfectly hard. Sharpening them adds a fringe and can move a letter. If the subject is type, read the blurry-text page and consider retyping. If the subject is a mark, read the logo page. This page is for a photograph whose focus was a little soft, not for a vector that was rasterized.

Unblur is the mode, and it is not a strength slider

FixPhotoQuality does not publish an amount from 0 to 100. Unblur is one credit, on the free tool, and the comparison is the control. If the result is too crisp, keep the original. There is no second knob that will give you half of what the model did. A second unblur pass usually traces the first pass and makes skin look embossed. One job, then a decision.

Order matters when the file is also noisy. Denoise first, look at a flat wall and a hair, then unblur only if the cleaned file is still soft. Unblurring first draws the noise into little edges, and the denoise that follows has to sand those edges off. Night photographs belong on the night page for that reason. A daylight portrait that is merely a little soft can start here.

The free download stops at 3,200 px on the long edge. A sharpened file that was already under that size downloads whole on Free plan. A 4× enlarge is a different mode, on Pro, and it is not required to see whether the sharpen was honest. Commercial use is allowed on every plan when you have the rights to the file. The upload and the result are deleted after 24 hours. A failed job returns the credit. The subscription fee is not refunded.

What a finished sharpen looks like at 100 percent

Open the slider and find three places: a catchlight in an eye, a fabric weave or a brick, and a smooth cheek or sky. The catchlight should stay a small shape, not a painted dot with a ring. The weave should break the surface a little more clearly than before, without a white trench on one side. The cheek should not gain pores that were not in the original, and the sky should not gain a contour line along a roofline.

If those three places disagree, trust the worst one. A skyline halo is enough reason to keep the soft file even when the eye looks better. Print size makes the halo easier to see, not harder. An 8×10 at 300 ppi wants about 3,000 px on the long edge, which fits in the free download. A poster does not. Do not enlarge a halo just because the calculator says you are short of pixels. Fix the edge, or decline it, before you buy size.

Face restore is the wrong tool for a portrait that is only slightly soft. It rebuilds features and can change the person. Unblur leaves the features where they were and only tries to make the existing blur less dominant. If the eyes have already turned to mush, the face page is the one to read, and it starts on Pro. This page stops at the honest edge.

A worked frame

Take a 2400 by 1600 daylight portrait that a previous editor already sharpened at a high amount. You can see a one-pixel bright line where dark hair meets a bright wall. Do not run unblur on that export. Re-export from the camera file with the mask at zero, then unblur once for one credit. The long edge stays 2400, inside the 3,200 px free download, so Free plan keeps the whole file. Check the hairline, a weave on a collar, and the catchlight. If the hairline grows a trench, the new export was still too crisp and the original camera JPEG is the file to keep. Commercial use is allowed if the sitting is yours to process. The pair of files is deleted here after 24 hours, so copy the keeper the same afternoon. A second unblur on the result is how skin becomes embossed. There is no amount slider to split the difference.