Drawing Tips: Preparing scanned lineart for digital coloring

I was gonna discuss flatting supposedly but I realized that before I do that, I should discuss how to prepare your scanned lineart for flatting and coloring. Now if you’re doing lineart digitally and have the layered file, that’s cool and all and you can skip this. However, if you drew the lineart traditionally or only have the flattened image of the lineart. You have to prepare it first.

I’ll be using this as a sample.

Big Sis so adorable… :’3

Step 1: Desaturate

Press ctrl+shift+u on Photoshop. Another method is open up Hue and Saturation.

Clip Studio Paint

You can also use ctrl+u (on either software) to open this window. Now, toggle the saturation all the way to the leftmost side.

What does this do: it converts all pixels into grays, white and black so that when you do level adjustments, it won’t get wonky. (I’ll be showing you the difference later on)


Step 2: Adjusting Levels

To do this simply press ctrl+L (on Photoshop).

Clip Studio Paint

Then adjust the toggles until you get a nice black and white lineart like in the image.

What does this do: This will remove the unnecessary gray pixels that got there when the image was scanned, leaving you a nice and crisp black and white lineart.

Now if you skipped the desaturate step, this is what will happen.

Since the image on the left side was not desaturated, unwanted blue pixels that have appeared and we don’t want that. What we need is black and white lineart for easier selection.


Now you have two options here.

Option 1: You can just set the lineart layer to “multiply” and proceed to coloring…

Multiply will disregard the whites of that layer so you can just add color underneath.

The downside to this is you can’t change the line color because that will require you to trace the image.

Option 2: Remove all the whites so that the black lines are the only thing that remains. This is a more preferable method. You change the color of the lines so on and so forth.


Step 3: Aliasing

This image should sum up the difference between Aliased and Anti-aliased.

Aliased (has black and white pixels only)
Anti-aliased (has some extra leftover gray pixels)

This will make your line crisp and way easier to use the downside is it may look a bit pixelly. It won’t be obvious if your scanned drawing is large (300-600 dpi) but it will definitely show on smaller images.

Here’s how to do it. I use different methods on Clip Studio and Photoshop which I will be tackling one at a time

For Clip Studio paint:

Go to Edit➡Tonal Correction➡Binarization

Adjust until you get desired thickness.

Time to remove the white areas.

Make sure you’re in the lineart layer. Then press ctrl-A to select the entire canvas. Then go to Edit➡Convert Brightness to Opacity

After that, you’ll have a nice and clean transparent layout to color!

Now it can be done with Photoshop as well but it has some complex methods than CSP.

Go to Image➡Mode➡Grayscale

Then go to Image➡Mode➡Bitmap

The image have to be in grayscale before converting to bitmap. Click “yes” when prompted and on the next window, choose “50% Threshold” then click OK.

Now just revert it back to RGB using the same method ( you have to convert it back to Grayscale first)

To get rid of the white lines:

Right click the layer and select Layer from Background

Go to Channels tab or you can just find it in Window➡Channels. There’s a circular icon tab there at the bottom. This will select the whites of the layer.

This will select all the whites of the color and then just press delete to remove them.

Clip Studio Paint

There you have it. Your lineart is nice and ready to be colored. Just be sure to save it as PSD or whatever layered file type you want. Next topic will be about different methods of flatting so see ya then!

Feel free to comment about your thoughts and if you have questions, just let me know as well.

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