A new version of Kenko’s 400mm mirror lens is to be released this month that is said to feature better anti-reflective coatings for improved flare performance. The Mirror Lens 400mm F8 N ll uses six elements in two groups and has a fixed F8 aperture. The closest focus distance is 1.5m/59in and the forward filter thread is 67mm while the rear takes a 30.5mm.
The lens is designed for full frame sensors but also comes in a longer version for mirrorless bodies. As it uses a T-mount, the lens can be supplied to fit cameras from nine different systems. There is no electronic contact between the lens and the body, and focus and aperture controls are all handled manually.
No price has been released yet, but more information is available on this translated version of the Kenko website news page. The product is set for release on the 15th September.