The largest series comprises collage drawings made entirely on location in Cambridge and other cities. For Butler, drawing is not a technical skill but a means of slowing down the world for long enough to look and to see. This is a thinking process and the drawings are a record of this. He carries with him bags of scrap paper, sorted by colour, a stick and a bottle of Indian ink. The collage is made first, maybe finding the patterns of an envelope and the colour of a train ticket that echo the colours and textures of stone in two adjacent buildings. The ink line is drawn over this. For Butler, one of the challenges and thrills of  drawing directly from life is to see how the white paper becomes street or building or sky by the use of a single mark or line.

This direct work on location informs the visual language of his printamking and artist's books