Rumors suggest Sigma is getting ready to launch a 50-100mm F1.8 lens for APS-C cameras. Full specifications and convincing images of the lens have been leaked, suggesting the lens will be part of the company's impressive 'Art' range. Such a lens would offer a fast partner to the company's 18-35mm F1.8 Art lens, giving the same angle-of-view, depth-of-field and total light gathering capability as a ~75-150mm F2.8 lens on full-frame.

Specifications reported on seem plausible, so we're looking forward to next week's CP+ show in Yokohama, Japan, to see if the rumors are true. We'll be reporting from the show, so stay tuned for all the details.

Lens construction (elements/groups) 21/15
Filter size 82
Minimum focus distance 95cm
Aperture blades 9
Length 170.7mm (mount not specified)
Diameter 93.5mm
Weight 1490g

 The site suggests a price of ¥167,400 (~$1500) and a launch date of April 22nd.