I made this tutorial long time ago, and im submitting it here now for every1 who is new to iso pixel art and need a little help
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Okey, First, you start with the lines of the thing you want to color.. I have made a cube, with a piece missing..
Then you make a ramp. A ramp is just a few colors, next too each other that get darker or lighter.. you can just pick a color, add it to your ramp, go to the color chooser and put the arrow a bit down so you have a darker color, and so on..
I have used 5 colors
Than pick a light source.. This is where the sun is in my case..
Its above the top, so that should be the lightest place.. shade it with the color under the lightest color..
than the color under that for the right side (the sun is on the right side) and then the left side with the color under that..
Now we are going to highlight our lines.. The lines that are fold out, so we see the outside of the corner should be light, the folds in, so we see the inside of the fold (in my case where the piece of the cube is missing) should be darker.. Pick a color that is one shade lighter than the lightest shade of the 2 your line is between or the one darker than the darkes shade of the 2 its between.. Now for the lines that do not fold, but where just the ending is from the cube, we shade with the darkest color as well, and tadaah, we are done!
This can be done with every isometric object.
Warning:
There is no correct version or wrong version.. there are only beautiful versions and not so beautifull versions of shading.. This is just my way of shading, but that doesnt mean its the only right, or the best way to shade.. There are alot of styles, and every1 does something else.. but this is just a very basic example, and good to start with