Luca Iaconi-Stewart's patience and attention to detail is amazing.

Today I feature my friend Paul Wang's sketchbook #23, an accordion sketchbook. Check out his blog and Flickr page for more sketches.

A reader asked me this question, so here's the video response to that. Having a larger number of colours means you can mix an even larger number of colours, but it will be challenging if you use so many colours in a painting. Usually, I use around 5 colours, so I don't really bring my big watercolour boxes out.