This tutorial will show how to colorize old black and white photos so they seem relatively realistic, while retaining their antique look. You may want to use this sort of technique if you are doing genealogy and want to modernize some old pictures, or for whatever other reasons.
Before and After
1) Add a color layer
Starting with a black and white photo, Create a new layer and fill it with a good base flesh tone. The color I'm using here is f30c0a2. Lower the opacity untill you can see the shadows of the background image how much you want. For the skin layer, I used 27.8%, other layers were different depending on what looked good.
*Tip* A good place to get skin colors is to pick a color from a real photo that has the color you want.
2) Add a layer mask
Right click the skin color layer, and add a Black layer mask. The color should disappear, and there will be a black preview box next to the skin colored box in the layers dialog.
3) Unmask the right places
Change your main color to white. Using fuzzy brushes, paint color onto the face. I used larger brushes for the middle, and then used the 2x2 fuzzy brush along the neck line and along the edge of her shirt and hair. If you mess up, switch your brush color to black, and paint black where you want the mask applied again.
The image will now look flat, cold and lifeless. We'll add some warmth to the image after we do the lips. Repeat steps 1-3 with a color for her lips, then continue below.
4) Add heat and life
Still working on the lips layer, switch to a large very fuzzy brush. Lower the brush opacity to 5% or so and paint some lip color onto her cheeks. Add a little bit to her chin, and along the curves of her neck. If you right click the lip color layer, and choose "Show Layer Mask" it should look something like this:
5) Repeat steps 1-3 as needed.
I used six colors for this image, but it is a relatively simple one. The nice thing about using layers and masks this way, is that it is easy to change the color of something quickly, and it is easy to fix mistakes as you go.
6) Optional: Use a radial gradient for the background
Create a new layer, as before, and paint the background a solid color of your choice. Using the gradient tool, create a radial gradient fading from the desired color to the solid background color. Apply a mask as in step 2, and then unmask around the image so that they gradient doesn't cover it.
Done!
Here's the final Gimp image if you'd like it:
http://stuporglue.org/gimp/colorize/final.xcf
Optional: Change layer colors
To change the color of a masked layer, right click the layer in the layers dialog, and un-check the "Edit Layer Mask" box. Pick a new color, and use the fill (bucket) tool to dump the new color on the layer.
