see also:

• Canon EF lenses
• Sigma 12-24mm f/4 DG HSM Art full frame lens
• Sigma 24mm f/1.4 DG HSM Art full frame lens
• Sigma 24-35mm f/2 DG HSM Art full frame lens
• Sigma 35mm f/1.4 DG HSM Art full frame lens
• Sigma 50mm f/1.4 DG HSM Art full frame lens
• Sigma 85mm f/1.4 DG HSM Art full frame lens
• Samyang 14mm full frame lenses

• 14mm f/1.8 ultra wide full frame lens in various mounts
• announced Feb 2017, available May 2017
• Sigma can optionally fit a rear mounted gel filter holder (FHR-11 filter holder) for around $US80
• compared with the Samyang 14mm f/2.4 SP the Sigma 14mm f/1.8 is bigger, heavier, more expensive and with more much coma and astigmatism below f/4 but is weathersealed, better build quality, has less vignetting and less distortion so better for lowlight photojournalism, moonlit scenes at 2 sec exposures, timelapse imagery or video

• 14mm f/1.8 ultra wide full frame lens
• weather resistant
• 16 elements in 11 groups
• 9 rounded blades
• no filter
• 95mm diameter x 126mm long
• 1.1kg! (plus MC-11 adapter if used on Sony E-mount cameras)
• $US1599

• https://www.dpreview.com/articles/1717621214/astrophotography-with-the-sigma-14mm-f1-8-art-lens
  • lots of vignetting wide open but the gradient is soft and coma is reasonably well controlled but bat wing shaped at the edges
  • does have lens flare issues with bright light sources such as a full moon
  • a reasonable choice for ultra wide angle astrophotography or aurora shots where the additional aperture would allow shorter exposure times
• https://fstoppers.com/gear/astrophotography-sigma-14mm-f18-dg-hsm-art-lens-and-coma-183601
  • see comments section regarding coma issues
• youtube: 14mm f/1.4 vs Rokinon 14mm lenses for astro
  • much better star shapes than the Sigma 20mm and 24mm f/1.4 lenses
  • not as sharp in corners as the manual focus only smaller, lighter, cheaper (half the price), Rokinon 14mm f/2.4
  • the manual focus Rokinon 14mm f/2.8 is far cheaper, smaller, lighter but does have much more vignetting, much poorer build quality and optical consistency between lenses, and over time with vibrations such as driving on gravel roads, tends to be subject to lens de-centering causing softness of image quality
• Youtube: 14mm f/1.8 for astro
  • perhaps the best 14mm astro lens, minimal coma which is gone by f/2.8
• https://www.camerastuffreview.com/en/sigma-lens-review/review-sigma-14mm-f-1-8-art-mc11
  • 1.75EV vignetting wide open and 1EV at f/4
  • sharpest at f/8 (f/5.6 in the centre)
  • 3% barrel distortion
• https://www.slrlounge.com/sigma-14mm-f-1-8-art-lens-review-the-new-champion-of-14mm-ultra-wides/
  • more coma and astigmatism than the Rokinon 14mm f/2.4 but less vignetting and distortion