Sigma's latest addition to its Art line of wide-aperture lenses seems like it's on the pricey side at $1,600, but when you consider that only Nikon offers a similar model for twice as much, this feels like a bargain if you can afford it.
Sigma plans to ship the 105mm F1.4 DG HSM full-frame lens in June in Canon, Nikon and Sigma mounts, with a Sony E to follow at an unspecified date.
A fast telephoto like this is a great choice for headshots with soft backgrounds, as well as moderate-distance wildlife photography, so long as the situation lends itself to a fixed focal-length rather than a zoom. On a camera with an APS-C sensor, its scene coverage is equivalent to 158mm (Nikon, Sigma, Sony) or 168mm (Canon).
The lens is big and heavy for a prime, though: 4.6 inches in diameter by 5.2 inches long (that's 115.9 by 131.5 millimeters) and 3.6 lbs (1.6 kg).