Article by Ey@el

Original en français

It's been a long time since my last photo editing tutorial. I must say after migrating to Linux, I had to learn how to use different graphic tools even though I've managed to get Paint Shop Pro 8 running with Wine (previously I've been using PSP X for many years but it doesn't work on Wine). So for this new tut requesting no additional plugin, I've used GIMP which is the default installed graphic program on most Linux distributions and is also available for Windows but you will should have no problem using it with any other image editor.

Materials

- a colour (or black and white) picture with good contrast and clearly defined lines

Instructions

1. Open a copy of the image you wish to manipulate.

2.  Apply effect Colours - Threshold (or Settings - Luminosity and contrast - Threshold if you're using Paint Shop Pro).

NOTE: I've kept default settings, but you may use a change the value for black pixels (left setting) until you're satisfied with the preview (for PSP, there's only one setting). If necessary, you should cover unwanted areas with black or white after applying the threshold effect.

For my second example, I've duplicated the original layer and applied the threshold on the top layer using value 100. Then I set this layer blend mode on Value (Overlay or Hard Light if you're using PSP). To enhance the effect, I've then applied several cosmetics improvements to the original bottom layer.

Easy peasy, yet the result really depends on your original as you'll quickly realise you won't get good rendering with every pictue, only with some. Why not using these bichromic pictures to create stencils, to print and handcolour them, use them as brushes in your graphic editior or turn them into vectorial images, etc. As always, your imagination.

Ey@el