The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sony 16mm F2.8 Fisheye and the Sigma 19mm F2.8 DN for their suitability to various photography scenarios:
Size and Weight Comparison
The weight of a lens is equally significant as its external dimensions, particularly if you intend to handhold your camera and lens combination for extended periods. Sigma 19mm F2.8 DN weighs 140g, 65% (260g) lighter than the Sony 16mm F2.8 Fisheye's weight of 400g.
Lens Mounts
The Sony 16mm F2.8 Fisheye has the Sony Alpha lens mount whereas the Sigma 19mm F2.8 DN has the Sony E lens mount. Some of the latest released cameras that are compatible with these mounts are Sony A99 II, Sony A68 and Sony A77 II for the Sony Alpha Mount and Sony ZV-E10 II, Sony A6700 and Sony FX30 for the Sony E Mount.
Sigma 19mm F2.8 DN is also available in Micro Four Thirds mount.
Focal Range
Sony 16mm F2.8 Fisheye is a prime lens with fixed focal lenght of 16mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
24mm.
On the other hand, the Sigma 19mm F2.8 DN is a prime lens with fixed focal lenght of 19mm which has an effective (full-frame 35mm equivalent) focal range of 28.5mm when used on a APS-C / DX format camera.
