The Bronica Zenzanon-S 150mm f/3.5 is a classic telephoto prime lens designed for Bronica’s 6×6 medium format SQ series (SQ, SQ-A, SQ-Ai).

• Field of View: Roughly equivalent to an ~80mm lens on a 35mm full-frame camera, making it a standard portrait lens for the SQ system.
• Shutter & Optics: Features an electronically controlled Seiko leaf shutter built into the lens barrel, enabling full flash sync at all shutter speeds up to 1/500s. Uses a 5-element optical design with a 67mm front filter thread.
• Characteristics: Delivers smooth background blur (bokeh) and flattering compression for tight portraiture and detail work.
• Distinction: Precedes the later PS series (which moved to f/4); the "S" version offers full-stop aperture detents and a slightly brighter f/3.5 maximum aperture.