The second generation of 7.5mm F2.8 has been optimized in the optical structure. Single glass with a higher refractive index is used in the front glass group to replace the first generation cemented glas. The rear group of optical glass is added with the HOYA ED glass, which effectively improves the chromatic aberration. The image quality of the lens has been improved accordingly. Under the premise of correcting various aberrations, the field of view angle has also been improved a lot; the polishing process of the glass is more precise and complicated than the previous generation. The optical structure of the entire lens still consists of 11 lenses, but the total optical length is shortened, making the lens more compact than the previous generation. The overall appearance continues the style of the first generation but still uses an all-metal mirror body. The difference is that the 7.5mm F2.8 Mark II adopts the shell oxidation process, and the lens mount color is replaced with electroplated tungsten steel color. Makes it more beautiful but also sturdy and durable; Newly adapted to Nikon Z mount, helps users more choices. Note: Because of the large shooting angle of the fisheye lens, the hood filter holder will block the imaging, so there is no filter holder, hood, etc. temporarily
