Kit Leese Artist and Printmaker 

Gouache, once known bodycolour, and used extensively by artists like Turner, is an ideal medium for painting detail in landscapes.

 

It is entirely water-based, and can be diluted just like watercolour, and used wet in wet to produce brilliant sky effects.

 

Its versatility means that dry brush work across an already painted surface is very easy to do.  I use Windsor and Newton Designers Gouache which has the same pigment as their watercolours, and can easily be mixed with them.