In the "lenses-that-make-you-go-mmmmm" department, Sigma adds to its collection of fast, premium-build Art lenses with the Sigma 50-100mm F1.8 DC HSM Art, the first medium telephoto zoom with a constant f1.8 aperture. That's the perfect focal range for portrait photography on a full frame camera, and more-or-less the equivalent of the staple 70-200mm f2.8 on an APS-C camera (75-150mm on Nikon and 80-160mm on Canon), a nice range for sports where you can get reasonably close.
It uses internal focus and zoom, which is nice for shooting movies, and incorporates a more compact version of the company's Hyper Sonic Motor. It's kind of heavy, at over three pounds (53 oz./1,491g), but that's about the same as the Canon EF 70-200mm f2.8. Its minimum focus distance is much closer at 37.4 inches/95 cm, and it's a little bit smaller, but not much. It will be available for Canon, Nikon and Sigma mounts.
Sigma did not announce any price or availability for the lens. Given Sigma's recent history of delivering nice lenses at a surprisingly low cost, I'm really curious about what the company plans to charge for it.
For Sony and Micro Four Thirds mirrorless cameras, the company is rolling out the Sigma 30mm F1.4 DC DN Contemporary, a fast wide prime that's part of its less expensive Contemporary line. That's the fastest aperture available in the 30mm-class of lenses short of the Sony/Zeiss 35mm f1.4, and it's likely to be far more affordable. Even Olympus doesn't offer any f1.4 lenses.
It incorporates a stepper motor, which generally aren't as zippy as the 'sonic versions (hypersonic, ultrasonic and so on), but still quiet enough for video. It's fairly small at less than 3 inches/7.4cm and can focus at just under a foot/30cm. Unfortunately, we have no word on pricing or availability for this one, either.
Finally, Sigma also revealed an EF/EF-S-to-Sony-E-mount converter, the MC-11, which has more intelligence than your average converter. The drawback is that it seems to be optimized (or possibly will only work with) Sigma's Canon-mount lenses. There's a display that indicates whether the lens and body are compatible and whether the firmware needs updating, and it has lookup tables for each Sigma EF-mount lens to optimize sensor-shift stabilization performance and lens corrections. No price or availability for this one, either.