GIMP Plugin Registry

This extension allows you to add dominants to your black and white (or colour) photos.
In the "Layer mask" mode the dominant is balanced with a mask, such that your whites remains whites.
The homepage is in Italian but you can see some screenshots and examples there. Please note also that the plugin is in English.

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This script does LAB sharpening using the unsharp mask in the luminance (L) layer. It decomposes the image into LAB layers, sharpens the luminance layer (using the supplied settings), and then recomposes the image. The interface is the same as the unsharp mask (radius, amount, threshold), but the filter is only applied to the luminance layer.

This plugin evens the tone of an image. It useful in photography for correcting weird light, and can hide skin blemishes.

The layers are not merged to allow opacity adjustments after the filter has been run.

Usually for a photograph, you'll want to use either the sharpen layer, or the "Soft Light" layer.  read more »