We've been shooting with the Sigma 24mm F2 DG DN 'Contemporary' on a Panasonic Lumix DC-S1R for the last week and, so far, the results are impressive. It's nice and sharp at the center, with little softness in the corners. Chromatic aberrations are well-controlled and sun stars are pleasant, though you'll notice some ghosting in places.

We'll be adding more photos to this gallery over the next several days, so keep your eyes on the homepage for those.