I am still a beginner with GIMP, so this is definitely not the voice of experience talking. Most of this I learned by trial and error and flopsweat. ;D I'm hoping this might save one or two of you the same frustrations I had.
TUTORIAL #1: Coloring with Layer Modes in GIMP
Here's the original cap she was working with:
Her original attempt to icon it looked like this:
In a conversation with me and a couple other icon makers, we were trying to explain how to fix the aspect ratio and the washed-out look of the faces, without losing the color. (I'm going to talk about text in the second tutorial, below.)
So first, we'll crop the picture, making sure that we keep the pic absolutely square:
Save it as a PNG (better quality). Now it's time to color.
I've found that an easy way to brighten colors and get them to pop is to do what I call my "3 Layer Screen-Overlay Technique"(TM). *g* Caveat: I like bright colors. I'm not too interested in sepia-toned or washed out colors. Those are both pretty popular right now, but to each his own!
1) Duplicate the cropped base three times by pressing the duplicate button.
2) Set the top layer to screen on the Layer Modes.
This is obviously too bright, so now we...
3) Set the middle layer to overlay.
Now you can duplicate that layer one or more times to get even brighter colors. Sometimes I have 2-3 screen and overlay layers in combination.
4) If you don't like the levels of either one, you can change the opacity with the slider on that layer:
On this one, I changed the opacity of the overlay to 50%. I could have also changed the screen layer to make it less bright.
5) Once you have the color/brightness you want, flatten the image:
6) Now it's time to resize to 100x100. I tried it from here, but the edges of Lois' hair looked oversharpened. EX:
Something that seems to work for me is blurring the image once or twice first, before scaling it down.
And now it looks like this:
Now I would probably do a few more steps, like brightening Lois' eye color, or making the sky bluer... or something. But that's the basic process.
TUTORIAL #2: Bordering text with layers in GIMP
In this tutorial, I'm going to show my method for bordering text, which works better for me than using the Stroke Tool.
Here is the original cap:
This is the original icon she made:
The coloring is nice and warm, but the text seems out-of-place.
So using the technique in Tutorial #1 above, I cropped and colored my own version:
Mine has a bit more redness in it - but it has much the same "warmness," so I'm going with that.
Okay, time to add the text.
1) I want to use colors from the newly colored cap - but I cropped out the blue in Clark's jacket! So I used Edit-->Undo History to get back to the original size:
2) After coloring with the three layers, I clicked the Foreground Color in the Toolbar, then used the color picker to select the red of Lois' lips, and the blue of the lightest part of the jacket.
3) Next, I selected Arial Bold 18 and the blue color to start, placing the text near the same area as the original icon.
The blue seems dark, but I decided to wait to see how it looked with the red border... Here's my method:
4) Right-click on the text layer, and pick "Text to Selection"
5) Duplicate the text layer, then right-click in the center of the highlighted text on the picture. Go to Select-->Border
Set the pixels at 2, and feather the border:
6) Now fill the duplicated text layer with red. Change the Foreground (FG) or Background (BG), then right-click in the center of the selected text again. Edit-->Fill with FG color (or BG if you changed that).
7) Move the filled text layer under the other text layer. Merge the text layer and the filled layer together by right-clicking on the top of the two layers you want to merge:
You get this:
While that's better, in my opinion, the text is still a bit out-of-place looking. So change the opacity to something lower (I chose 50%), like this:
Or set the Layer Mode to Screen:
Or Grain Extract:
Just play around with different modes and opacities. :)
Other GIMP users, I definitely want your opinion on things you would have done differently, and specific steps! It will help both of us. :)