by Vivien Park
![](https://4.bp.blogspot.com/-LyAJffjn0Js/T5b6Ak4Tr_I/AAAAAAAAGMI/5lK-7j5FDos/s1600/Screen%2520shot%25202010-03-19%2520at%25201.04.png)
"Andy... 3/15/2010 4:12:17pm Los Angeles, Ca" by Burton Machen. Source: Burton Machen
When a work of art is shown, it no longer belongs only to the artist. And when it is placed in public space, a co-authoring process unfolds and evolves over time as the elements and passersby leave their marks.
Photographer and street artist Burton Machen posted two-toned images of political figures, celebrities, friends and other personalities on walls throughout New York City and Los Angeles. The results are interactive collage and assemblage — part expression, part commentary, part documentary.
Burton Machen’s "Urban Evolution: Portrait Projects" will be on view at New York’s Hionas Gallery until May 19.
![](https://4.bp.blogspot.com/-LyAJffjn0Js/T5b6Ak4Tr_I/AAAAAAAAGMI/5lK-7j5FDos/s1600/Screen%2520shot%25202010-03-19%2520at%25201.04.png)
"Andy... 3/15/2010 4:12:17pm Los Angeles, Ca" by Burton Machen. Source: Burton Machen
When a work of art is shown, it no longer belongs only to the artist. And when it is placed in public space, a co-authoring process unfolds and evolves over time as the elements and passersby leave their marks.
Photographer and street artist Burton Machen posted two-toned images of political figures, celebrities, friends and other personalities on walls throughout New York City and Los Angeles. The results are interactive collage and assemblage — part expression, part commentary, part documentary.
Burton Machen’s "Urban Evolution: Portrait Projects" will be on view at New York’s Hionas Gallery until May 19.