Well, it's not much of a 'tutorial' really, I'm horrible at writing descriptions... And this is ment for those who are familiar with Adobe and knows how to use the colour picking tool and so on...blabla...

Basically, don't be afraid to use multiple layers, merge them as you go, and spend some time playing with multiply (layer) and opacity. Oh, and the zoom can be your best friend sometimes... ;>

Hopefully this will give you an insight in how I would paint an eye... there are ofcourse better, and easier, ways to paint an eye, but if you always take the quick ways you might miss some information and you won't learn as much as you do if you struggle with a picture.

Last hint: ALWAYS avoid pure black or pure white, only use pure white on absolute highlights ; on other areas, tint it with greyish blue and or greyish red. If you use the color picker you will notice that almost no pixel in this painting that looks black or white really is. Actually, most colours should contain some grey if ever so slight.

To answer some questions : I use lots of layer, not just one or two!! I work with each layer until I'm satisfied, up to three layers at a time, then I merge them.

The grey I'm talking about is when I pick a color (I use the 'palette' thing that pops up when you click on one of the colour choice squares... in lack of better terms, I raelly don't know what it's called ) I never choose the 'corner' colors (white-intense color-black). I choose tinted versions.

Good luck!

Note : As *slshimerdla said, eyes have tiny flicks of other colours in them. That is very true. Mine isn't uber-realistic so I kinda let that slip... Thanks *slshimerdla !!