How can I fix an out-of-focus blurred photo in Photoshop?

  • How can I fix this picture? Somebody else took this picture and well he wasn't able to do it very well, and it's blurred.

    the photograph in question

    I have photoshop

    An intentionally blurred area of an image is going to be much more blurred than a slightly out of focus image, yet might be easier to recover *if* you know what algorithm was use to produce the artificial blur. These are two totally different ways the blur was created.

  • mattdm

    mattdm Correct answer

    8 years ago

    I don't have Photoshop, but there's an ancient open source project called refocus-it (for iterative refocus), which uses some of the same techniques as Photoshop's new-in-CS6 deblur feature. This should give better results than sharpening with unsharp mask or a high-pass filter. Below, I chose (after some experimentation) a radius of 3.1 and (since the image is very noisy) a noise reduction level of 4000, and 100 iterations, giving this result:

    refocus-it'd

    There are a few weird flat artifacts on the faces, and some clear jaggies around the edge of the flag, but this was a really quick pass. Plus, I'd be surprised if the decades-newer technology in Photoshop can't do a better job. In any case, I think it's at least better than the sharpened result overall. If you don't mind spending a lot of time at it, I might try one approach in one layer and the other in a different layer, and selectively (and softly) erase so that you get the best result in each area of the photo.

    You can get similar results with the "Sharpen (Richardson-Lucy)" filter in G'MIC. Here's the sample photo run through that with 100 iterations:

    g'mic version

    And again, some by-hand touch-up and blending will make it look nicer. It's not ideal, but decent for social media sharing and just fine for small prints.

    I tried it out in CS6 and it still looked a bit like pushing it through the stained glass filter... :) Not much you can do I suppose, it's started very soft.

    I should add that, with the open source project at least, it's _crucial_ to get the sliders right; if the radius isn't correct, you get strong ringing artifacts, and if the noise suppression is too low you get speckles everywhere but too high and you get _additional_ blur rather than sharpness. And as far as I know it's basically trial and error to get those right settings.

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Content dated before 7/24/2021 11:53 AM