[ tascha.ch ]

Since I tend to work my linework into the painting I need it on a seperate layer and here is a fast way to do just that:

I am working from very rough pencil sketches - this however will even work better if you plan to color inked lineart.
First of all, scan your linework as big as possible but at least at 300 dpi. However if you are working in print resolution you will have to scan your sketch big anyway. After scanning, this is what you will have: One single background layer with your lineart.

To start seperating I first set my background colour to the colour I want to work with.
Afterwards hit ctrl-a, ctrl-x and ctrl-v. This process will cut out the line-work and add it to a new layer. As a finishing touch I adjust the brightness and contrast as needed (Image -> Adjustments -> Brightness/Contrast… ).

Next, I adjust the channel tab (normally hidden beneath the layer one) by clicking the little circle icon on the very left bottom, effectively selecting all the white in your picture. If you can’t find that particular tab then just go to “Window” (on the top menu) and choose “Channels”

After hitting delete it will leave you with your separated line-work on a transparent layer. It will probably look quite faded out if you haven’t adjusted the contrast and the brightness but we are going to correct that in the next step.

Finally, I change back to the normal layer tab and click the little lock icon on top (make sure you get rid of the selection and that you still are on the linework layer). By adhering to this procedure I ensure the transparency will be preserved enabling me to paint over my sketch lines with any colour � either to adjust it to better fit the actual painting later or to make it darker again.

And this is what my linework would look after going over the lineart layer with a red brush: