The Sigma 50mm f/1.4 DG HSM Art has been a staple among the gear collections of many photographers since its release back in 2014. It’s no accident, either. It’s an excellent lens offering fantastic results. But today, it has one big flaw. It’s designed for DSLRs and not mirrorless cameras. Sure, you can use adapters, and there is an E-Mount version, but it’s still just basically the DSLR lens with an adapter bolted onto the end. It looks like Sigma’s looking to finally replace this lens, however, with a 50mm f/1.4 DG DN Art lens designed specifically for mirrorless cameras. Naturally, this means Sony E and Leica L mounts. As is often the way, a few specs of the new lens have leaked in advance of an official announcement, but there’s no word yet on whether this lens will be the first of Sigma’s rumoured expansion into Z mount.

There are no images of the lens, and while there aren’t many specs, they highlight the most important details that most of us want to know. How big is it? How heavy is it? What filters does it use? And what’s the minimum focus distance?

Lens construction: 14 elements in 11 groupsShortest shooting distance: 45cmMaximum magnification: 1:6.8Number of aperture blades: 11 (circular aperture)Filter diameter: 72mmSize: 78.2 x 109.5mm (L mount)Weight: 670gLens hood: LH782-02Lens cap: LCF-72 III

If the specs are accurate, the new lens isn’t simply the old optical formula in a new housing with new electronics. The old lens contained 13 elements in 8 groups, while this one says 14 elements in 11 groups. The rumoured DG DN also contains two more aperture blades, so the bokeh will be a little different, too. The new lens is also a little bit narrower in diameter but longer in overall length. It does look as though it’s lost a significant amount of weight, though, dropping from 815g down to 670g. There’s no word yet on exactly when we’ll hear an announcement from Sigma, so that means we also don’t know when it’ll actually hit retailers. Nor do we know how much it will cost, but for reference, the Sigma 50mm f/1.4 DG HSM Art for DSLRs launched at around $949 and it still sells for that price today. If a new DG DN lens for mirrorless isn’t around the same price, I don’t expect it would be too much higher. [via Asobinet]