Yongnuo will soon announce a new YN 14mm f/2.8 ultra-wide prime autofocus lens. Pricing and availability are not yet available. Stay tuned for updates.
Yongnuo YN 14mm f/2.8 lens design:
Yongnuo YN 14mm f/2.8 lens MTF chart:
Additional pictures:
Yongnuo lenses are available for sale at B&H and Amazon.