Step One: Preparing the Outline
[current materials] Photoshop (v 6.0), obviously. And we are working with 'Schulich Sketch', a cute Weiss Kreuz fan art by my friend A-chan.
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1)
Begin.
Open the sketch or image you want to cel-color. I've opened a small file drawn by A-chan called 'Schuldich'. Feel free to swipe it for practice, but don't claim it as your own, please.
Open it up, and immediatly cut and paste [Control (Ctrl) 'X', Control (Ctrl) 'V'] the image into a new layer. If the Background color isn't white, get the paintbrush or paintbucket tool and color it white.
Right click on the layer and select 'Layer Properties' to entitle it 'Outline'. This is merely for organizational purposes. Later on, you'll have a ton of layers. Giving them names really helps.
2) Clean up the sketch.
You need to clean up the outline now, and get rid of that nasty yellowish tint. Most scanners do not do sketches justice, so we have to fix them up a little first.
Go to Image>Adjust>Brightness/Contrast.. and plug in +25 into both options.
Doesn't the sketch look much cleaner now? You can also crop the sketch if you need to get rid of unwanted white space, but you don't have to.
3) Make it transparent.
This step is needed in case you need to color the sketch later to fit the image. Trust me, it seems like you don't need this step now, but it will save you a lot of suffering. ^_~
Go to the Channels window and hit the 'select all channels' icon [figure below]. All of the black areas should be selected. You'll see it, don't worry. ;)
Hit DELETE. Yes, delete. The image will fade out a lot. Don't worry, this is supposed to happen.
Now go back to your Layers menu, make sure the Outline layer is still selected, and click out, so that the selected areas, those dotted lines, disappear.
Look at the Layers menu again, and with the Outline layer selected, select the Lock Transparent Pixels box, as shown in the picture below.
Now select a paintbrush, any size (though I recommend large), and color the sketch BLACK. It should be back to it's nice, clear, clean black color now. ;)
The reason you did this extra step, instead of just multiplying the layer, is so that you can color your outline later so that it blends in with the picture better. Trust me, it's worth the effort. See, go choose another color, and try coloring it red or blue. And back to black. See what I mean?
NEXT! >> Coloring your Clean Sketch
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