MS Optics notes in their press release that the lens itself features four elements in four groups, with a wide open aperture of F/4.5 and minimum aperture of F/16. The Perar Ultra-Wide 17mm f4.5 Retrofocus can also focus on subjects as close as 0.4m meters to infinity.
On a very interesting note, the company states in the press release that there is a significant amount of vignetting when the lens is shot wide open. It’s not common for a company to highlight what most would consider to be a huge flaw in the press announcement, but I suppose we should give them credit for being up front about it.
According to the MS Optics, the lens is at its peak performance at F/8, with little vignetting or other optical abnormalities like coma and softness.
Due to the lenses being handmade the stocks will be limited and the lens will be available in batches as they are completed. If you are interested in this lens you will be able to purchase through Japan Camera Hunter for around 80,000 yen, or somewhere in the $700 to $,1000 range.