Sharpening a Photo with the High Pass Filter

30 November 2007

I originally found this technique at Luminous Landscape. It gives better results than the unsharp mask and its effect can be removed from the picture at any time.

Proceed as follows:

  1. In the Layer palette select the layer to be sharpened (most probably the background layer).

  2. Duplicate this layer (Layer > Duplicate Layer).

  3. Give a name to the new layer, e.g. High Pass.

  4. Ensure that the new layer is selected in the Layer palette, then apply the High Pass filter (Filter > Other > High Pass).

  5. Set the filter radius to 10 then click OK.

  6. Select Hard Light in the blend mode drop-down menu (the one in the top-left of the Layer palette).

  7. Play with the Opacity slider until you’re pleased with the result.

The following two pictures show the effect of high-pass sharpening with a radius of 10 and layer opacity set to 50%:

Sharpening (Original)
Original picture
Sharpening (High Pass)
High Pass sharpening

To disable the sharpening effect, simply click the eye on the left of the layer in the Layer palette. To remove it permanently, delete the layer.

Some references: