see also:

• Canon EF lenses
• Canon EF 24-70mm f/2.8L lenses

• announced Feb 2017

• 24-70mm f/2.8
• HSM AF
• optical image stabiliser - said to be 3EV
• 19 elements in 14 groups incl. 4 ASPH and 3 HLD
• internal focus
• 82mm filter
• 9 rounded blades
• close focus 0.37m giving 0.21x macro
• 88mm x 108mm long

• https://www.lensrentals.com/blog/2017/07/lensrentals-com-review-the-new-sigma-24-70mm-f2-8-dg-os-hsm-art-series-lens/
  • although a touch shorter, it is 20% heavier than the vII Canon
  • unlike Canon or Nikon lens, if it doesn't lock AF, it gives up instead of continuously hunting for it
  • almost non-existent lateral CA
  • doesn’t match the sharpness of the Canon and Nikon, especially wide open at 24mm