Mixing a comfortable wide-angle design with an ultra-fast maximum aperture, the 17mm f/1.4 lens is designed for use with APS-C-format mirrorless cameras and provides a 25mm equivalent focal length. The optical structure of this lens is 9 elements in 8 groups and the angle of view is 81° .
Characterized by its bright f/1.4 maximum aperture, this lens is adept at working in low-light conditions and also affords increased control over depth of field for selective focus control. 
It's a fast and portable lens well-suited to landscape, nature, and street photography.

APS-C 50mm F1.2 adopts the optical structure of 7 elements in 5 groups. The minimum focusing distance is only 0.5m.Length: 60mm, Width: 62mm. The equivalent focus length of full frame is about 75mm——Professional assistant for your Portrait photography.

The TTArtisan M50/0.95 has an optical structure of 11 elements in 8 groups, including 1 large-sized aspherical element and 5 high refractive elements to ensure the image sharpness at wide open. As the largest aperture stop of full-frame photographic lenses, F0.95 perfectly explains the meaning of creamy bokeh and the maximum light it can capture in low light condition. The filter thread of this lens is 67mm. With a size of 74mm*72mm, it only weights 673g. It is still a lens of exquisite size and moderate weight among F0.95 series.

From Petapixel
By JARON SCHNEIDER
2020.12.10

From Photolari
By Iker Morán
2020.10.27

From DPReview
By BASTIANK
2020.10.19