Full-frame and 46mm imaging circle Maximum micro-contrast control and ultra-low chromatic aberration for unparalleled image quality Large aperture of T1.9 and soft bokeh for beautiful background separation Precisely engineered to minimize focus breathing, maintaining a consistent field of view during focus adjustments Matched in weight and size to other NiSi Athena Lenses 77mm filter thread and matched aperture and focus rings Focus ring with 300° rotation and fluorescent focal scales Offers unparalleled image quality, flexibility, and creative control