The V&A museum was one of the first in the world to collect photography and since 1977 it has been charged with maintaining the national collection of the art of photography in the UK.  But not until now has a gallery at the museum been devoted to housing one of the leading collections of the world.  The collection is so vast that it will be rotated through the gallery every 18 months. After 150 years of amassing photographs it now has over half a million photos, so that task of choosing only 80 to fill this new and compact photographs gallery is a challenging one for the V&A.