The Lens Industar-61 L/D 55mm f/2.8 (Russian: "Индустар-61 Л/Д 50/2.8") is a kit lens for FED rangefinder cameras. The application of lanthanum glass made it possible to get rather high resolution while preserving a simple optical scheme and a 2.8 lens speed (44/30 lines/mm center/edges). Vendor: FED Ukraine S/N#9234404 Lens Mount: M39/L39 Focal range: 55mm Max.aperture: 2.8 Min.aperture: 16 Aperture blades: 6 Preset aperture: No Optical design:4 elements in 3 groups: Tessar variant. Resolution (center/edge): 44/30 lp/mm Minimum focusing distance: 0.1m Filter Ø: M40.5.
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