With the Color tools you can manipulate image colors in several ways:
Modify the color balance: Section 5.2, “Colour Balance”
Adjust hue, saturation and lightness levels: Section 5.3, “Hue-Saturation”
Render into a greyscale image seen through a colored glass: Section 5.4, “Colourise”
Adjust brightness and contrast levels: Section 5.5, “Brightness-Contrast”
Transform into a black and white image depending on pixel value: Section 5.6, “Threshold”
Change the intensity range in a channel: Section 5.7, “Levels”
Change color, brightness, contrast or transparency in a sophisticated way: Section 5.8, “Curves”
Reduce the number of colors: Section 5.9, “Posterise”
Convert all colors to corresponding shades of gray: Section 5.10, “Desaturate”
Except Desaturate and Posterize, color tools have presets: saved tool settings that you can retrieve later.
Three elements:
Presets: this drop-down list shows you the existing presets. Every time you change tool settings, a new preset is automatically saved, with date and hour; you must be aware of that, to preserve your computer memory.
The cross: clicking on this cross opens a window where you can save current settings under the name you want.
The small triangle: clicking on this triangle opens a small menu:
Three options:
Import settings from file
Export settings to file
Manage settings