Brightin Star MF 50mm F1.05 Full Frame

The Brightin Star MF 50mm F1.05 Full Frame is an ultra-fast manual focus standard prime for full-frame mirrorless cameras. It is offered for Sony E, Canon RF, Nikon Z and Leica L. With an angle of view of 43 degrees it covers the classic normal perspective, and the F1.05 maximum aperture is aimed at low-light work and very shallow depth of field.

Optical design

According to Brightin Star the lens has 10 elements in 8 groups, including high-refractive (HR) and extra-low dispersion (ED) glass, with multi-layer coating against flare and ghosting. The aperture runs from F1.05 to F11 and is built from 15 blades, an unusually high count that should keep the opening close to circular when stopped down. The filter thread is 58mm and the minimum focus distance is 0.57 m.

Focusing and handling

Focusing is fully manual. Brightin Star describes the aperture ring as de-clicked, which allows smooth changes during video. The lens has no stabilizer and no autofocus motor, so the camera's focus aids are the practical way to nail focus at F1.05, where the depth of field is razor thin.

Build and size

The manufacturer lists an all-metal barrel. Weight depends on the mount: 606 g for Sony E and Leica L, 614 g for Canon RF and 632 g for Nikon Z. Brightin Star's hand-measured drawings give a diameter of 68 to 70 mm and a length of 80 to 84 mm, so these figures are approximate.

Where it fits

The database has no predecessor for this lens. The closest rival is the 7artisans Photoelectric 50mm f/1.05, which offers the same maximum aperture on the same four mounts. Other fast manual options are the TTArtisan 50mm f/0.95 and the Mitakon Zhongyi Speedmaster 50mm f/0.95 III, while the TTArtisan 50mm f/1.2 is a smaller and lighter step down. Autofocus alternatives include the Sony FE 50mm F1.2 GM and the Sigma 50mm F1.2 DG DN Art.

Pros and cons

Pros

• Maximum aperture of F1.05 for very shallow depth of field
• 15 aperture blades for a round opening
• De-clicked aperture ring for video use
• Four mounts, including Leica L

Cons

• Manual focus only
• About 606 to 632 g is heavy for a normal prime
• Minimum focus of 0.57 m is relatively long
• No stabilizer, no weather sealing in the manufacturer's data

Verdict

The Brightin Star MF 50mm F1.05 Full Frame is a niche lens for photographers and video shooters who want maximum light gathering and a very shallow focal plane at a modest budget. The data sheet shows a solid metal build, a generous blade count and a respectable 10 element construction. The trade-offs are weight, manual focus and a long close-focus distance.