The Pentax SMC FA 645 150mm f/2.8 (IF) is a premium autofocus telephoto lens designed for Pentax 645 medium-format cameras. This fast, short-telephoto prime delivers a 35mm-equivalent focal length of approximately 118mm, making it ideal for portraiture and selective subject isolation with its generous f/2.8 maximum aperture. The lens features an inner focus (IF) system that maintains consistent physical length during focus adjustment, ensuring stable handling and optimal balance throughout your shoot. Premium optical construction includes high-refraction low-dispersion glass and extraordinary-low dispersion elements that minimise colour blurring and chromatic aberrations whilst delivering sharp, high-contrast images with impressive clarity. The multi-coated optics provide excellent light transmission and flare resistance, allowing for consistently clean images across varied lighting conditions. With a minimum focus distance of just 1.2 metres, this lens excels at close-work photography whilst maintaining its characteristic three-dimensional rendering and creamy bokeh character that medium format is renowned for. Supplied with a generous lens hood featuring a PL filter operation window for comfortable use of circular polarising filters when composing through the viewfinder.