Episode 164: High Pass Sharpening July 29, 2011

from Meet the GIMP· ·

Sharpening is a part of nearly every image processing. Selective sharpening allows to sharpen the important structures without to “enhance” the noise in the image. Already in Episode 6 I have shown a way to do this. And here is another way, High Pass Sharpening. It is often used in Photoshop tutorials and has no standard entry in the GIMP menus. One step involves blurring – and this leads to a lot of different possibilities to change the effect. I explore asymmetric sharpening by blurring only into one direction. Of course there are plugins available at the GIMP plugin registry. …



Sharpening is a part of nearly every image processing. Selective sharpening allows to sharpen the important structures without to “enhance” the noise in the image. Already in Episode 6 I have shown a way to do this. And here is another way, High Pass Sharpening. It is often used in Photoshop tutorials and has no standard entry in the GIMP menus. One step involves blurring – and this leads to a lot of different possibilities to change the effect. I explore asymmetric sharpening by blurring only into one direction. Of course there are plugins available at the GIMP plugin registry. A description of several sharpening methods is in our Wiki, I’ll add the high pass method today. I got the recipe for this from a (very good) German book by Jürgen Wolf. The TOC 01:48 Good German book: Jürgen Wolf, GIMP 2.6 02:00 GIMP 2.8 release late in 2011! 02:20 Preparing the image 02:40 Rotate 03:30 Crop 04:10 Contrast, black point and white point adjustment with the curves tool 05:30 The recipe for Highpass Sharpening 05:40 Duplicate the layer twice 05:50 Invert the colours 06:00 Set layer mode to Grain Merge 06:10 Blurring 07:00 Merge the top layer down and set the layer mode to Overlay 07:50 Adjusting the effect with the opacity of the sharpening layer 08:00 Sharpening in only one direction 09:50 What is Grain Merge doing? 11:00 How does this work? 14:50 Scripts at the https://registry.gimp.org Meet the GIMP Video Podcast by Rolf Steinort and Philippe Demartin is licensed under a Creative Commons Attribution-Share Alike 3.0 Germany License. Permissions beyond the scope of this license may be available at https://meetthegimp.org.