Viltrox 20mm f/1.8 Overview
Offering a broad field of view and a bright design, the PFU RBMH 20mm f/1.8 ASPH from Viltrox is an ultra-wide prime lens for Sony E-mount mirrorless cameras. The wide-angle design and fast f/1.8 maximum aperture make it well suited to astrophotography use, as well as landscape, interior, and architectural shooting. Its optical design incorporates a series of aspherical and low dispersion elements, which reduce spherical and chromatic aberrations for sharp, well-corrected imagery with accurate color rendering. An HD Nano multi-layer coating has also been applied to suppress flare and ghosting for improved contrast when working in strong lighting conditions. The lens has a manual focus design, which permits working with subjects as close as 9.8" away, and its 14-blade diaphragm contributes to a pleasing bokeh quality. Additionally, it is constructed from brass for durability and smooth operation.
 
Ultra-wide prime is designed for full-frame Sony E-mount mirrorless cameras; however, it can also be used with APS-C models where it provides a 30mm equivalent focal length.
Bright f/1.8 maximum aperture suits working in difficult lighting conditions and also offers increased control over depth of field.
Four extra-low dispersion elements, one double-sided aspherical element, and one element made from highly transparent glass all contribute to reducing a variety of aberrations in order to produce a well-corrected image with accurate color and high sharpness.
HD Nano multi-layer coating has been applied to individual elements to reduce flare and ghosting for improved contrast. Also, this coating is water resistant to help protect the exposed surfaces from moisture.
Manual focus design, with a 148.5° focus throw, permits working with subjects as close as 9.8" away.
Engraved focus distance and depth of field scales benefit working with prefocus and hyperfocal focusing techniques.
A 14-blade diaphragm contributes to a pleasing bokeh quality.
Brass lens barrel construction realizes a physically durable design that also affords smooth operation.
Included lens hood helps to prevent flare and also affords some protection to the bulbous front element. Additionally, a filter adapter ring is included for mounting 82mm screw-in filters.