Masking using a vector program (Drawplus SE, freeware)

Open your scanned image with all the drawn pieces

I simply use a rectangular selection tool to select the part I want (Rectangular Marquee Tool, drag a rectangle around the part), copy it (from the Edit menu select Copy, or use Ctrl+C), and paste as a new image (File menu, New, then Image from Clipboard). It’s quick, easy and I don’t have to think, which is a real bonus for everyone as I’m told the noises can be distracting.

If you’d like to see this in action, I’ll be putting up tutorial movies of cutting and masking (the next step) in both Serif PhotoPlus SE (capable freeware, available from http://www.freeserifsoftware.com/, thanks to Serif, although Serif’s full commercial versions do a lot more for quite a reasonable price) and also in Adobe Photoshop Elements (very common amongst home users, I’m told).
You can do the same in other software if you have another image editing program you prefer to use.

Unfortunately, simple layer masking was one of the functions Adobe removed when creating Photoshop Elements, although you can still find it in the full version of Adobe Photoshop.

Fortunately, there is a workaround. We can add another layer with a mask, then group the layers and make use of the other layer’s mask.

Firstly, add a new solid colour fill layer. The colour of the new layer is not important.

If your image layer is below the new colour layer, just drag your image layer up to the top.

Note the mask for the colour layer.

Select (highlight) the image layer, and press Ctrl+G
(Alternatively, from the Layer menu select Group with Previous)

The image layer should appear indented with a small bent arrow indicating it is grouped with the layer below.

I like to add a couple of "contrast" layers below my working layers, so I can see the masking as I add it.
I add these as two more solid fill layers, not grouped.
I usually add a bright green layer to see the masking.
I also add a black layer, to show up any wisps or crumb of semi-transparent background I might miss when I’m masking against bright green.

Make sure your mask is selected, not the image, by clicking on the Layer mask thumbnail. (1)
When you select the layer mask, you should normally see black and white for foreground and background. (2)
Make sure your foreground colour is black (swap if need be using the little double-headed bent arrow between the two black and white squares) .

Pick the brush tool (3) and adjust the size of the brush if necessary, and any other options (I find a slightly soft-edged brush often works better).

As you paint into the mask layer with black, you are hiding part of the layer, revealing the contrast layer underneath.
If you look closely at the Layer Thumbnail, you will see wee are not actually erasing or removing the background, just hiding it.

Imagine light shining through a stained glass window, creating a coloured image on a wall.
Now imagine holding up a cutout painting/drawing stencil between the window and the wall, so only some of the image reaches the wall.
That’s similar to what we are doing. Our mask layer is the stencil and we are not touching the original image (the window), only the parts you see (the image on the wall).

If you make a mistake and mask part of the image you don’t want hidden, simply swap your foreground paint colour to while, and paint it back in again – it’s still there, just hidden.

Actiually, because the hand-drawn shape is itself imperfect, a little bit of imperfection in the masking won’t hurt a lot, whether you hide a little bit of the edge of the outline, or leave a slight white edge around it.

At this point it looks like the mask is complete (with a green background), but change to the black contrast background we created earlier, and you’ll possibly see that some of the masking needs work.
Here I need to clean up that wispy pale stuff left in the mask, by painting some more black into the mask, possibly using a harder-edged brush.

Clean up as necessary, switching between the green and black contrast layers.

The background "contrast" layers have served their purpose, you can turn off their visibility now.

In Photoshop Elements, use the File menu and select Save for Web…

Export the image as a .PNG-24 file + transparency (some programs show this as a 32-bit .PNG file, which is the same thing).
With the contrast layers hidden and transparency selected, you should see a checkerboard background.

Then all you have left to do is complete masking all the other pieces, heh-heh.

Open your scanned image with all the drawn pieces

I simply use a rectangular selection tool to select the part I want, copy it, and paste as a new image. It’s quick, easy and I don’t have to think, which is a real bonus for everyone as I’m told the noises can be distracting.

If you’d like to see this in action, I’ll be putting up tutorial movies of cutting and masking (the next step) in both Serif PhotoPlus SE (capable freeware, available from http://www.freeserifsoftware.com/, thanks to Serif, although Serif’s full commercial versions do a lot more for quite a reasonable price) and also in Adobe Photoshop Elements (very common amongst home users, I’m told).
You can do the same in other software if you have another image editing program you prefer to use.

With the Rectangle Selection Tool, drag a selection box around the piece you want to cut out.

From the Edit menu, select Copy.

From the Edit menu, select the Paste sub-menu, then click on As New Image

I like to add a couple of "contrast" layers, so I can see the masking as I add it.

I usually add a bright green layer to see the masking.
I also add a black layer, to show up any wisps or crumb of semi-transparent background I might miss when I’m masking.

Drag the contrast layers below your image layer.

As you turn the background transparent using masking, these contrast layers will show up.

Make sure your image layer is selected, then add a Layer mask (use Reveal All).

Make sure your mask is selected, not the image, by clicking on the Mask Thumbnail.
When you select the layer mask, you should normally see black and white for foreground and background.
Make sure your foreground colour is black (swap if need be using the little double-headed bent arrow between the two black and white squares) .

Pick the paintbrush tool (I find a slightly soft-edged brush often works better) and adjust the size of the brush if necessary.

As you paint into the mask layer with black, you are hiding part of the layer, revealing the contrast layer underneath.
If you look closely at the Layer Thumbnail, you will see wee are not actually erasing or removing the background, just hiding it.

Imagine light shining through a stained glass window, creating a coloured image on a wall.
Now imagine holding up a cutout painting/drawing stencil between the window and the wall, so only some of the image reaches the wall.
That’s similar to what we are doing. Our mask layer is the stencil and we are not touching the original image (the window), only the parts you see (the image on the wall).

If you make a mistake and mask part of the image you don’t want hidden, simply swap your foreground paint colour to while, and paint it back in again – it’s still there, just hidden.

Actiually, because the hand-drawn shape is itself imperfect, a little bit of imperfection in the masking won’t hurt a lot, whether you hide a little bit of the edge of the outline, or leave a slight white edge around it.

At this point it looks like the mask is complete (with a green background), but change to the black contrast background we created earlier, and you’ll possibly see that some of the masking needs work.
Here I need to clean up that wispy pale stuff left in the mask, by painting some more black into the mask, possibly using a harder-edged brush, or using the hard-edged pencil tool instead of the paintbrush tool.

The background "contrast" layers have served their purpose, you can turn off their visibility now.

Export the image as a 32-bit .PNG file (some programs show the .PNG export as 24-bit + transparency, which is the same thing).
In Serif PhotoPlus SE, I use the File menu and select Export Optimizer…
When 32-bit is selected, you should see a checkerboard background.

Then all you have left to do is complete masking all the other pieces, heh-heh.

If you’re planning ahead for cut-out animation, you can actually draw your characters in handy cut-up pieces to begin with.

Here we have Larry the line-drawing already drawn in pieces. You can draw the complete character on one sheet then trace over it, moving the tracing paper before tracing each separate piece.

I draw one piece of every limb joint with a complete rounded end so when the limb bends you don’t see a break in the outline or in the joint. The other piece (which will be on top of the rounded end) has a blank end so the joint is less obtrusive.

Some people prefer to cut out the pieces while they are still in paper format, and scan them against a different coloured background.
I prefer to leave everything in one piece – it’s easier to file, and I can label the pieces on the paper so I don’t lose track.

This is where I think cut-out animation is superior to traditional animation.

Traditional animation is all about simplification. Every button, frill, pattern and texture needs to be re-drawn over and over, possibly on every frame. So, the advice always given is to simplify your character to the essentials.

However, cut-out animation can use all the textures and details you want, providing it doesn’t obscure the character or the action. You can add all sorts of decoration to your character pieces, because you won’t be re-drawing it, just moving it around.

Want an extra button on that sleeve? Why not!
Want a lace edge? Add it on!

However,I recommend keeping your character obviously stylized. The more realistic your character looks, the more realistically animated the audience will subconsciously expect it to be (later we’ll look at the exception of obviously cut-up photographs).
More stylised characters can get away with more stylized animation, which is great for the home animator.

In this case our character, Larry is mostly coloured by pencil on paper, which adds it’s own texture, with some skin flood fills added on the computer because I didn’t like the pencil colours.

Now that I look at him again, he could be stylised a lot more, but we’ll forge on ahead anyway.

What resolution should you scan your character at?
The answer, unfortunately, is "it depends".

What it mainly depends on is your final output size. If you were going to output your animation as 788×576, and you want your character to take up most of the screen vertically at some stage from the waist up, that mean you want the waist-up shot to occupy almost 600 pixels (rounding off 576). If your character has been drawn at 3 inches high, you want that 600 pixels in the top 1 and 1/2 inches. That means you need to scan your character in at 400 dpi (dots per inch) to fit 600 pixels in 1 and 1/2 inches.
If you’d drawn your character 6 inches high (yes, I can hear those jokes in the back row), you would only need to scan them at 200dpi.

Cut your scanned image into separate pieces (more details in the next couple of lesson sections, also available as video tutorials).

I prefer to use layer masking to separate the cut-out piece from its background.
Layer masking is like holding a stencil between a stained glass window and its image on a wall – it doesn’t affect the original image, so if I make a mistake and erase too much I can easily correct it, unlike using an eraser tool where I could delete something permanently.

Usually you paint the mask with black where you want the image to become transparent, and white where you want the image to remain opaque.
(More details on masking in the next couple of lesson sections, also available as video tutorials.)

Many programs will show you a checkerboard background to indicate where the image is transparent.

Some programs don’t allow you to mask a "background" layer which always remains completely opaque, so you may have to either "promote" your image to a normal layer or duplicate the background image layer then either delete the original or turn off its visibility.

I prefer to place bright green and completely black layers behind the layer I am masking, so that I don’t miss any little scraps of background that I am masking.

Save your pieces to either 32-bit PNG files or 24-bit PNG plus transparency (two ways of saying the same thing, butin different software).