London, July 12 : American R `n' B singer Beyonce Knowles has reportedly told photographers on her current world tour not to take pictures of her from behind, as she sweats so much.

Beyonce, 27, is wowing crowds on her `I Am... Sasha Fierce' global jaunt, but her dance routines are so energetic that she is left dripping wet afterwards.

Sources have revealed that the singer wants that photographers only shoot from certain angles to preserve her modesty.

"Beyonce's costumes are so tiny and her choreography is so complicated that inevitably she sweats," the Daily Express quoted a source as having told the New York Daily News.

"It looks pretty gross, so no one is allowed to shoot her from that particular angle any more," the source added. (ANI)