Developed in the 1840s, this lens design is prized for its distinctive swirl bokeh pattern, a dreamy look modern filmmakers are actively reviving.
The Petzval lens dates back to Joseph Petzval's 1840 calculation — one of the first mathematically optimized lenses ever. Its hallmark: the so-called swirl bokeh, where out-of-focus areas rotate in a spiral around the sharp center. What was considered an optical aberration back then is now a coveted aesthetic effect.
Optics
The classic Petzval design consists of two lens groups with an air gap in between. The field curvature — the actual "flaw" — creates the swirl. The further from the center, the stronger the distortion of the bokeh.
Modern Interpretations
Lomography has reinterpreted the design with the Joseph Petzval Focus-coupled Bokeh Control Art Lens: a coupled system where the bokeh character changes with the focus. For cinema use, companies like ARRI offer tunable Petzval rings with their Hero Look Lenses — the DP can adjust the intensity of the swirl directly on set.
Focus-Coupled Bokeh Control
The latest generation of Lomography Petzval Art Lenses solves an old problem: with earlier versions, the focus had to be readjusted after every bokeh change — a dealbreaker for video work. The new Focus-Coupled System decouples the two: the focus remains stable while the bokeh ring rotates through seven intensity levels. Five focal lengths (27mm f/2.0 to 135mm f/2.8) cover a complete cine set, and the gears are standardized across the series. PL mounts are in development.