How can you use a camera if you can't see? Over 30 blind and visually impaired adults from the UK, Mexico and China have been trained in sensory photography techniques to create and experience photos.
As an exhibition of some of their work opens in east London, Matt Daw, from the UK charity PhotoVoice, explains how people like Gary, Alistair and Marcus were taught how to use a camera.
Sights Unseen runs from 19 - 23 January at The Association of Photographers Gallery in central London.
All images copyright Photographer/Sight of Emotion/PhotoVoice. Music courtesy KPM Music.
Slideshow production by Caroline Hocking and Paul Kerley. Publication date 20 January 2010.
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