Watercolour and Gouache
Watercolour techniques (transparency) and gouache (opacity) are favoured during his travels, periods during which, Jean Hirtzel accumulates notes on coloristic atmospheres. Compact material and rapidity in technical execution make them the ideal tools for the production of sketches and studies. Many sketchbooks constitute a painted journal.
Whether in the studio or travelling, Jean Hirtzel also uses egg tempera mixed with earth and charcoal to explore ancient techniques that are particularly relevant to the expression of archaic pictorial forms.
Wash drawing is also frequently used in his ink drawings, even some of his hand-written pages are reworked pictorially. Indian ink and watercolour can be mixed. Wash drawing, like watercolour, does not allow a way backwards and its use must be both detailed and rough.