We have recently received signed stock of Ken Grant's Flock, a superb colour photo essay, following the final five years of the last urban livestock market in Britain.  There's also another new Ken Grant title, No Pain Whatsoever, a black-and-white observation of the people and urban landscape of his home town Liverpool.

The Harry Callahan exhibition continues at the Tate Modern to 31 May.

"Photographs are little pop songs" says Alec Soth in an interesting article on What Makes a Good Photograph.