The way water and paint work together is a beautiful thing to behold. By wetting a page first and then introducing drops of watercolour paint, you'll bear witness to a blending of colour that no digital tool can successfully reproduce. The effect is so real, but what about those of us who prefer to work digitally?
Sadly there isn't a digital tool that effectively reproduces watercolour effects that rival the real thing. Painter has approached the issue, but the general opinion is that it only achieves limited success. The app produces a nice bleeding effect, but it feels a little laborious to control. To give the software engineers credit, it really is an impressive effect, but unfortunately still doesn't have that natural sense of randomness. As digital artists wishing to incorporate a real-world effect into our work, we're once again faced with the obvious decision of using the real thing.