Sigma 24-70mm f/2.8 IF EX DG Lens for $749 – Deal Alert November 29, 2013 By Eric Reagan B&H has the Sigma 24-70mm f/2.8 IF EX DG lens for $749 (reg. $899) as another of its Black Friday deals. The lens is available in Canon, Nikon, Pentax, Sony and Sigma mounts. The deal includes 4% rewards from B&H. Check it out here at B&H Photo.