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Unsharpen Mask / Luminosity

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  • Unsharpen Mask / Luminosity

    If you want to apply sharpening to an image and do not want to switch to lab mode, here is another method to do so...

    Unsharpen Mask settings:

    Divide the output resolution by 200 and this determines your radius.
    Threshold: Setting of 4-8 reduces graininess in flesh tones.
    Adjusting amount: should result in the max perceived sharpness without any degredation noted.

    Duplicate your image layer and apply a considerably higher amount of masking to the file than normal.

    Go to Edit and select Fade Unsharpen Mask. Move the slider to 0 and change the mode to luminosity.

    Use the slider to increase the percentage of the effect until the image's apparant sharpness is satisfactory and click OK.

    This method results in a cleaner and cripser file with far fewer color irregularities than when masking is applied directly to the RGB or CMYK image.

  • #2
    Perfect. Now everyone can find it easily. This one I am definately going to try. When I do I will try to post some examples.


    • #3
      You're already earning your stripes. Appreciate the detailed steps.

      After finish the sharpening in Lab, do you normally convert back to RGB (or CMYK)?



      • #4
        Danny, the tip from Rachel was specifically avoiding a change to LAB mode, as the task was only a simple luminosity sharpen.

        Many LAB edits can be simulated in RGB or CMYK modes by using a layer blend in Color or Luminosity (or even hue or saturation to do HS edits instead of affecting both at once as in color blend). There is also the fade command to color or luminosity modes too (fade simulates a duped layer with blending mode or opacity modifications). Many tools have a blending mode option too.

        There are issues with moving a file out of RGB but these are not as great as in CMYK where custom edits and black plate data can be significantly altered.

        LAB is great for extensive retouching or for major colour moves which really depart from the original. LAB is not generally recommended for most users as a general workspace and there are many pros/cons with LAB which others with better knowledge and writing skills have written...

        Some links to more links on further reading on the two subjects of Sharpening and LAB mode:


        Stephen Marsh.


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