From Panasonic:

The Panasonic Lumix S Pro 50mm F1.4 is a large-aperture fixed focal-length with impressive image quality and rugged lightweight design, interchangeable with L mount camera bodies. Its 50mm focal length and F1.4 high speed ensure versatile use and stunningly high resolution with descriptive performance From center to corners of your images.

• 50mm fixed focal F1.4 L-Mount lens, Leica Certified for Lumia S Series full-frame L mount Mirrorless cameras
• 13 lenses in 11 groups; 2 aspherical lenses and 3 ED (extra-low dispersion) lenses effectively suppress both axial chromatic aberration and chromatic aberration of magnification
• Lens focusing – a double focus system combines a linear motor and stepping motor to achieve sensor Drive At a maximum speed of 480 FPS for fast, high-precision autofocus
• 77mm diameter filter with an 11-blade circular aperture diaphragm
• Dust/splash/freeze-resistant design withstands use under harsh conditions for high mobility

Official Website

Panasonic Lens Firmware Updates

Reviews:

• Cameralabs: Panasonic Lumix S Pro 50mm f1.4 review so far, Gordon Laing, Jun 2019
• Photography Blog: Panasonic Lumix S Pro 50mm F1.4 Review, Mark Goldstein, Mar 2019
• The Phoblographer: REVIEW: PANASONIC 50MM F1.4 LUMIX S PRO (A BEAUTY OF THE L MOUNT), Chris Gampat, Feb 2020

YouTube:

• Richard Wong: Panasonic Lumix S Pro 50mm f/1.4 In-Depth Review, Feb 2019
• Jared Polin: WATCH THIS Before BUYING the “OVERPRICED" $2,300 Panasonic 50mm f1.4 L-Mount Lens | REVIEW, Aug 2019
• Matti Sulanto: Lumix S PRO 50mm F1.4 –Really IMPRESSIVE lens, Aug 2019
• Pav SZ: Panasonic Lumix S PRO 50mm f1.4 - Is it really worth more than $2k?, Oct 2020
• Evan Ranft: The Lumix 50mm f1.4… Overrated and Overpriced?, Mar 2022