Sony's ultra-thin APS-C pancake prime, one of the smallest E-mount lenses ever made.
The Sony E 16mm f/2.8 is one of the earliest E-mount lenses, launched in 2010 alongside the original NEX cameras. As an ultra-thin pancake design providing a 24mm equivalent wide-angle perspective, it makes Sony APS-C mirrorless cameras remarkably compact and pocketable.
Optical quality is mediocre by modern standards with soft corners and visible distortion. The centre is acceptable but this is not a lens for critical work. The ultra-wide adapter (VCL-ECU2) widens it to 12mm equivalent. Build is minimal plastic. There is no optical stabilisation.
Sony E mount in APS-C format, 49mm filter thread. This has been largely superseded by the Sigma 16mm f/1.4 DC DN Contemporary which is dramatically better optically and two stops faster, though physically much larger. The Sony remains unique for its pancake form factor.
Very cheap used. Check the autofocus motor and front element. The lens is primarily of interest for its compact size rather than optical quality. For image quality the Sigma 16mm f/1.4 is the better choice; for pocketability nothing beats this pancake.