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The Askar 71F is a versatile and compact flat-field refractor designed for both astrophotography and visual observation. With a thoughtful balance of optical performance and practical features, the 71F delivers sharp, wide-field images right out of the box, making it ideal for enthusiasts seeking quality without complexity.
The 71F features a quadruplet air-spaced apochromatic lens design that includes one ED glass element to effectively reduce chromatic aberration. Its built-in flat field design eliminates the need for an external flattener or complex backfocus calculations. Simply attach your camera to the included adapters and focus to start imaging with excellent edge performance across a 44 mm image circle, including full-frame sensors.
With a 71 mm aperture, 490 mm focal length, and f/6.9 focal ratio, the 71F strikes a sweet spot between wide-field astrophotography and enjoyable visual use. The package includes a photographic extension tube with M48×0.75 and M54×0.75 adapters plus a built-in 2″ filter thread, making it easy to connect DSLRs or astronomy cameras. For visual observing, included accessories — an 8 mm eyepiece, a 20 mm eyepiece, and a 1.25″ 45° erecting prism — provide correct orientation and comfortable viewing for celestial targets and terrestrial subjects alike.
The mechanical design keeps weight and size manageable: the OTA weighs approximately 2.5 kg (about 3 kg with tube rings and dovetail plate), and a retractable dew shield shortens overall length for travel. The 2.4″ dual-speed rack-and-pinion focuser offers 1:10 fine adjustment and a 360° rotator at the rear for precise framing. Two finder bases on either side of the focuser plus a handlebar mounting slot expand accessory options, while the 230 mm Vixen-style dovetail plate with 1/4″ and 3/8″ screw holes allows direct tripod attachment.
Accessories and companion products confirmed for this item.
