High Pass

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Revision as of 15:02, 17 January 2012 by WikiSysopPS (talk | contribs) (Sharpening)
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Sharpening

Almost all scanned images and photos require at least a bit of sharpening. What is sharpening?

Consider the image below of a dark grey circle on a light grey background...

High pass 01.png

This is a 'conceptual cross section' across the point marked with a red line:

High pass 02.png

A sharpen will identify all regions of high lightness contrast and accentuate the lightness values at the border:

High pass 03.png

This is what such a sharpen will look like (before left, after right).

High pass 04.png