When taking a photograph of a very green tree against a very blue sky I noticed my shadow and the shadow of the trees on the road. Earlier I had taken a photograph of a blackbird - but with only a small camera and without my glasses I had failed to see a goose sitting on the sand behind it. The images influenced the writing of some words which were recorded as a spoken word track

And then weeks later having forgotten again about shadows I hear for the first time about a woman photographer called Vivian Maier     
Her photographs are brilliant and a film about her was screened at the 2013 Toronto Film Festival    
Looking for more information I found a link - one of many - and included in the images was a self portrait in which she uses a shadow on the ground . I was unable to find a free link to the original Toronto Film Festival Documentary but it is available on Amazon and her official site is http://www.vivianmaier.com/