text: Buy Your Mom a Sigma? | DSLRBodies | Thom Hogan
  Let's quote the press release: "Sigma...today announced a special Mother's Day promotion, offering incredible savings on its award-winning Art lens line. Beginning May 3, 2018 and running through May 14, 2018, anyone looking to treat the mother in their life, or even themselves, to a gift that will help capture life's precious moments can save up to $100.00 USD on some of Sigma's most sought-after Art lenses." [emphasis added]
  At least they mentioned "or even themselves." That would be most of you ;~)
  I just got through looking closely at five of the 15 lenses on sale, and have reviewed six of them at this point (the two I looked at but haven't reviewed yet are the 24-35mm f/2 and 24-70mm f/2.8). So at this point I'm tried a bit more than half of the Art lenses.
  I'll agree with Sigma's assertion that they achieve excellent sharpness. Indeed, often I'd have to agree with their claim of "outstanding sharpness." That's been a solid trait of almost all the Art lenses to date. I'm less likely to agree with Sigma's claim of "dreamy, ethereal bokeh." Perhaps they dream differently than me; and I'm not sure they mean "intangible," which is is one of the definitions you'll find for ethereal. Still, these lenses don't have bad bokeh, at all. Just different than you find on the fast Nikkors.
  With US$50 to US$100 off the retail price for those 15 Sigmas until May 14th, that makes them even better values than they already were.
  DX shooters: Yes, I know the f/1.8 zooms have a short 2x range that's not quite the perfect range you're looking for. But these are among the best lenses that are DX. D500 shooters need to be aware that the outer edges of the focus system don't produce good results on the 18-35mm, but still, that doesn't stop me from recommending it. And the 50-100mm f/1.8 is truly the best telephoto zoom we've seen for DX.
  FX primes: There hasn't been a dud in the bunch, and all these Art lenses are already cheaper than the Nikkor equivalent. Getting some extra discount is just icing on an already tasty cake.
  FX zooms: The two you're most likely to be interested in (the 24-70mm f/2.8 and 24-105mm f/4) are, unfortunately, the least impressive of all the Art lenses I've tried to date. The gems in this bunch are the 14-24mm f/2.8 and the 24-35mm f/2, I think.