But why would you want to draw animation by hand, if vector drawing offers so much more control? Well, handdrawn animation has a spontaneity which is hard to reproduce with vector animation. And handdrawn animation is the most basic and direct form of animation. You see exactly what you draw. There is no manipulation or limitation by software.
In Photoshop, Gimp, or any other similar image editor, create as many image layers as there will be keys in your animation. Now do the following for each layer, starting with the lowest layer for frame 1:
- draw your frame in the current layer
- change the transparency of the current layer to 50%
- select to the next higher layer as the current layer
- if there are more than two layers visible, make the lowest of the layers invisible
Import the PNG files with the image sequence import script (Scripts -> Image -> Import Image Sequence), and rescale the animation (Animation -> Rescale Keyframes) for the Switch Layer animation channel, and drag the keys in the channel so it animates correctly. Copy keys if you want to animate a repeating sequence.
Draw the animation in your favorite image editor first with outlines only, as a line test. If this line test is correct, fill the outlines for each image. Make sure all files have the same width and height, so there will be no errors in the registration of the frames. You can always resize the switch layer in AS to combine handdrawn animation and other types of animation and stills.


Now, if you want to trace the images, go right ahead. However, there will always be some loss of quality and spontaneity of the straight ahead animation.
Here's some other animation:
