The PLx2 is an optical extender that doubles the focal length of 35mm PL-mount lenses. The PLx2 features high-index, low-dispersion glass to ensure the highest possible resolution and contrast with minimal optical degradation. The optical design is optimized for digital cameras and lenses at focal lengths of 50mm and greater. At wider focal lengths, sharpness and contrast generally improve as the aperture is stopped down, although some lenses perform equally well throughout the zoom range. While most extenders can only physically fit on a limited range of lenses, the design of the PLx2 allows it to accommodate the widest array of PL-mount lenses of any doubler. Compatibility is achieved with a deep-set optical assembly that accepts lenses with deep protruding rear elements. The PLx2 is also designed to mount to any digital cinema camera with a native PL-mount. It will also clear the spinning mirror on ARRI and Aaton 35mm cameras. Optically, the PLx2 projects an image with a diameter large enough to cover all commonly used 35mm formats, including 5K on RED Epic and the full 4:3 frame of ALEXA. Minimum image circle projection is 32mm. Maximum input aperture is F1.8.