The major complaint about Nikon’s huge NIKKOR Z 58mm f/0.95 Noct lens is the fact that it is missing an autofocus motor. According to Nikon, including the AF motor would have caused the size of the lens to increase far beyond imagination
The revelation came during an interview published by Japanese publication Xitek. In an issue devoted to the development of the Nikon Z-mount, the publication was opportune to interview some of Nikon’s engineers together with Hiroyuki Ishigami and Tomoharu Fujiwara.
While discussing the latest Noct lens, Xitek mentioned the lack of autofocus to which Ishigami-san admitted that “at the beginning of planning, I hoped to adopt AF,” Fujiwara-san explained the reasons why MF was ultimately chosen.
“Of course we have also studied AF, and driving the focus lens itself can be done. But the action is quite slow, not as fast as manual operation. At the same time, the increase in size is far beyond imagination. It cannot be driven by the existing ultrasonic motor, and a larger actuator must be arranged outside the lens.
Therefore, if you really want to achieve AF in the f/0.95 lens, this optical type will not work. You need to reduce the focus lens and use the internal focusing method. But using this method will result in a longer overall length, which means that peripheral components will also increase, and the lens will still be larger and heavier than it is now.
Even if such a lens is made, even if the product is very special, it may not be established as a product, so we gave up AF.”
While this lens is just a statement piece, it still had to be usable. If you are thinking the current version is too large for a standard focal length, you can imagine what it would be like to add an internal focusing motor capable of moving that much glass. In addition, it would have made this already expensive lens($8,000) more expensive for Nikon owners.
(source Peta Pixel)
