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Welcome to the brand new Askar FRA series! The FRA, which stands for "Flat-field Refractive Astrograph", is a quintuplet refractor telescope with built-in flat field correction. Although the name implies it is a telescope specifically designed for astrophotography the FRA can of course also be used perfectly for visual observation. The FRA series is one of the best prized and most versatile and high quality astrophotographic telescopes in the current astronomy market.
The quintuplet FRA optics are excellent in controlling and avoiding chromatic aberrations and provide pinpoint stars across the field. This modern optical design is coupled with well built mechanical features: A retractable dew shield, a 3" rack-and-gear-based high-precision dual speed focuser with integrated 360-degree rotator, M68×1 thread, a 2" adapter ring and a 1.25" visual adapter. It's worth mentioning that FRA series refractors have a pair of fashionable-looking and multifunctional patented tube rings. Various practical accessories can be attached on three sides of the tube rings!
The optional reducer is equipped with fine focal adjustment function for more precise calibration in practical observation or sky imaging.
These portable and versatile astrographs are beautiful to look at, look through and work with. It's definitely your intimate helper for your visual and photographic observations.
Askar FRA telescopes are available in different focal lengths offering a very interesting range for the amateur astronomer to choose from!
Askar FRA300
The Askar FRA300 Pro is a small but powerful 60mm F/5 Petzval astrograph. 60mm aperture, 300mm focal length at F5. The star image is sharp and delicate. At the center of its field of view, the RMS radius can reach 2um! It performs excellent with full-frame chips and supports 44mm imaging, which is a breakthrough for astrographs for amateur astronomers in this price range.
Askar FRA400
The Askar FRA400 is a 72 mm F5.6 (400mm) quintuplet astrograph which has adopted a modern optical triplet design with 2 ED lenses and a 2 ED element flattener that gives a flatfield of 44 mm.
Askar FRA500
Askar FRA500 boasts a quintuplet air-spaced APO optical structure, a "three plus two" Petzval lens combination. The 90mm front lens group consists of three lenses (including two pieces of ED glass) for excellent correction of aberrations. The flatfield corrector is composed of two lenses with an image circle of 55mm, at a focal length of 500 mm.
Askar FRA600
The ASKAR FRA600 is a 5-element apochromat according to Petzval with 600 mm focal length and the focal ratio f/5.6. The aperture is 108 mm. The triplet lens has two special ED glasses for an image free of chromatic aberration. The 2-element corrector is permanently installed in the tube and corrects an image circle up to 66 mm in diameter. And a lot of back focus space for all your needs.