pixel fairy wrote:
> is seems you cannot do to the three color channels what you can to any other, such
> duplicating a color channel is usefull for things like masking out complex
>selections (like hair)
Color channels are special; you can't get there from here.
But you can come close. Here's a few exercises.
0. Open an RGB image.
2. Pick any decomposition into Red Green Blue; Hue, Saturation, Value....
3. OK (Decomposing...)
4. You now have three or four greyscale images which can be readily fashioned
5. Layers->Layers, Channels, and Paths...
6. Use the image menu to select the various decomposed greyscale images
7. Now you can drag-and-drop or copy and paste your decomposed greyscale images back
onto the original to create additional layers, channels, alpha masks....
Or you can mess around with them with levels and curves first, for all
kinds of odd and interesting selection tricks.
Be good, be well