Tutorials: Extract grayscale image
Alrighty then, so next up I want to prepare a grayscale image for coloring so that I'll be able to do my flats underneath the original and have control over the line, grays, etc.
I begin with the scanned, cleaned image already in CMYK, and copy the whole canvas (CMND+A, CMND+C).
I then create a new Channel, which by default is named as Alpha 1.
Easy enough, I then paste the image on the Alpha 1 Channel, and invert the image (CMND+I).
I head over to Layers, and erase the image from the background, puff!
After that, I make a new layer, where the original image will go.
I go to Select > Load Selection, and choose the Alpha Channel from the dropdown menu.
This makes a selection from the original grayscale artwork we have sitting around on the Alpha 1 Channel.
I then fill the selection with Edit > Fill > Foreground Color (CMND+F5), and deselect the selection.
And well...there you have it, I guess.