Tuesday, May 08, 2007

Color Me, pt. 1

In response to some questions about computer coloring, here's a tutorial on the method I've been playing around with lately:

1. Draw the most awe-inspiring murder machine imaginable.

2. Scan it into the computer. Even though it's black and white line art, I recommend scanning it as grayscale art, at 600 dpi (dots per inch, y'all). 300 or even 150 will do, but why skimp? Ain't like pixels cost money.

3. Why scan it in as grayscale? As you can see, even a drawing made with thick black ink on clean white paper actually has a lot of other value information. That is, there's a range of grays. I don't want the computer making judgment calls as to which bits of gray are black, and which are white. It'll get most of it right, but it lacks finesse. Instead, I do that by going into Levels (under Image/Adjust in Photoshop), and move the little arrows around until I have exactly the black and white lines I want. This can take well over 6 seconds.

4. To make sure your lines are absolutely Black and White, convert the image to a bitmap. This is a good time to use the eraser tool to clean up any schmutz.

5. Convert the bitmap back to grayscale.

6. Convert the grayscale to RGB.

If these three steps seem like a run-around, let me explain: Bitmaps are files composed solely of black pixels and white pixels. Converting the file to a bitmap eliminates any little gray pixels you might not have spotted. Your lines are now completely crisp, and this will be a big help at a later stage. But you can't do much editing to a bitmap, so we convert it back to grayscale. This, in turn, allows us to convert it to RGB, which gives us the option of adding color. Once you've re-grayscaled you bitmapped line work, try not to drag it around, or resize it, or rotate it or anything, because those gray pixels will sneak back in.

7. Now, go the Layers palette and duplicate the background layer.

8. On the duplicate layer, take the pencil tool, and use a black line to close off any open areas, such as the hair in this image. Anywhere that two colors will meet in the final image should be outlined. Additionally, switch the pencil to white and open up lines that are breaking up areas that will be the same color in the final piece, such as where the eyebrow overlaps the hair.

More tomorrow!


Avram Grumer said...

Instead of going grayscale to bitmap back to grayscale, you can save a step by using the Threshold command (Under Image->Adjustments).

Pulpatooner said...

Good to know, Avram!

That's the thing about Photoshop: it's so rich that there are dozens of different ways to do anything. Many of my habits were formed in the dark days before Layers (what was that? Photoshop 3? Back then, Photoshop was a giant perforated cylinder we crammed into our steam-powered Babbage engines), and I'm sure there are much more efficient ways to accomplish just about everything I do. I hope folks will volunteer other shortcuts that pop up along the way!

The Codester said...

I've just learned more in 30 seconds of reading than I have in 3 years of college! My tuition payments should really be going strait to you Joel.

Stephanie Han Windham said...

Heh, you're looking strangely Mr. Rogers-esque these days...not that there's anything wrong with that!

Pulpatooner said...


Considering you've had three classes with me, the fact that you learned more in one blog-post may not be a ringing endorsement of my teaching methods. But, I'll still take those tuition checks.


You know, I almost drew myself wearing my blue canvas tennis shoes, as well. I... I just might be Mr. Rogers!

Also, it looks like I'll be at San Diego this summer. Are you and Curtis planning on dropping by the Con?

Evan said...

oh! i'm so excited about the riveting conclusion!!

p.s. you make yourself look so old! i always imagine you in my mind's eye as a spritely 25 year old!!

p.p.s this drawing would be sure to win the FACA this round if you entered it!

Pulpatooner said...


I purposely hagged myself up here in order to throw off the stalkers. Now, they'll all be looking for a soft-bellied, weak-chinned man of middle-years, instead of the bronzed, flaxen-haired He-God that I actually am.

Evan said...

smart move!

Unknown said...

Seriously... Thanks for posting this. I am STILL learning from you... geez.. quit already. :D

(hope you and your love are doing well)

Pulpatooner said...

Sorry, Michael, but signing up for one of my classes is a lifetime commitment. When you're old and wrinkled in a retirement home, making cut-paper decorations during "Craft Hour," I reserve the right to show and start critiquing your scissor technique.

Unknown said...

old... ?
wrinked... ?
when I'm... ?


now Craft Hour... hmmm? THAT sounds like an idea I can sink my elmers glue tip into! :D

I always look forward to Priddy critique... what would Joel say during a craft hour... I am truly curious...

I think if the nurses forced me into a situation like that during retirement I would shuffle my way out of the room and impale myself on a dull child-safe knife.

hmmm... I imagine THAT would be entertaining to witness... a weak old man killing himself with a dull blade... HA!!! the LONGEST death EVER! YAY!

Pulpatooner said...

That's a lovely image, Michael. I think it's a Flash animation waiting to happen.