Askar FRA500 Quintuplet APO Refractor
The Askar FRA500: The "Goldilocks" of the Flat-Field Refractive Astrograph Line!
The third entry within the Askar FRA telescope series, the FRA500 refractor is nestled amid the FRA400 and FRA600, striking a balance between powerful optics and ease of transport! This “goldilocks” telescope demonstrates the quality craftsmanship of the FRA series within a highly manageable and compact form factor, opening the doors to breathtaking images no matter where you go. Additionally, it's full support for medium-format sensors offers compatibility with a variety of advanced imaging trains for bright, captivating images of the cosmsos. Versatile, portable, and showcasing remarkable performance, the Askar FRA500 is an invaluable addition to your astroimaging toolkit!
The Askar FRA500 90 mm astrograph boasts a 500 mm focal length and f/5.6 focal ratio, making it an excellent choice for astrophotographers in search of next-level deep-sky imaging. FRA is short for "Flat-Field Refractive Astrograph", marking its ability to deliver tack-sharp stars across some of the largest sensors on the market today. This is thanks to the ingenious optical design—five elements effectively correct the incoming light for outstanding color accuracy and sharpness. In the sweet spot of not too big and not too small, this Askar FRA500 is compact and lightweight enough for travel, without a compromise in performance. Whether setting up in your backyard or on-the-go, you can expect remarkable results, no matter where your astroimaging journey takes you! Additionally, Askar has loaded this refractor with key inclusions to get you started. Tube rings, a Losmandy dovetail, a dual use handle bar, and plenty more comes standard within this package. A choice astrograph designed for astrophotographers seeking power and precision, the Askar FMA500 is a must have!
Flat Field Imaging for Medium-Format Sensors—Right Out of the Box!
As a quintuplet astrograph, the Askar FRA500 offers striking clarity within your frames! The five internal glass elements are arranged in a “three plus two” Petzval lens configuration, three in the front and two in the rear. The front lens group consists of two pieces of extra-low dispersion (ED) glass, a premium substrate selected to deliver the utmost definition and color accuracy. These five lenses are fully air-spaced and meticulously aligned to correct the incoming light with a high degree of precision—eliminating chromatic aberration and providing an inherent flat field. This flat imaging field spans a whopping 55 mm image circle, offering sharp stars across medium-format sensors! Rest assured knowing just about any camera sensor is compatible with the Askar FRA500 thanks to its sizable image circle. Another key benefit of this Petzval design, there is no need to fumble with backspacing calculations. As long as your imaging train can reach focus, feel confident knowing the entire field of view will be in focus as well. Without a need to fidget with spacers and adapters, just attach your camera and you’re ready to image!
A Pragmatic Refractor Built to Perform
High optical precision, versatile in nature, and ready for travel, the Askar FRA500 is a standout solution for astrophotographers in search of remarkable results! Whether you aim to capture vast, colorful nebulae or wish to look beyond our Milky Way towards distant galaxies, this multifaceted astrograph has you covered. Read on as we take a deeper dive into the additional aspects of this FRA500, highlighting its various imaging capabilities, travel-friendly, yet robust design, as well as the key inclusions found within this package!
Suitable for a Imaging a Broad Range of Celestial Objects
Equipped with a 500 mm focal length, an extensive variety of targets are available for capture! This well-rounded astrograph is wonderful for framing a host of targets such as the Cygnus Wall, the Trifid Nebula, the Eagle Nebula, and plenty more. Distant galaxies such as M81 & M82, the Triangulum Galaxy, and the Leo Triplet fit nicely within the frame as well. The rated 90 mm aperture is wonderful for collecting ample light on these targets for bright, detailed images. With a 500 mm focal length and 90 mm aperture, the Askar FRA500 astrograph features a resulting focal ratio of f/5.6. Four conical camera adapters come standard within this package (M48, M52, M54, and M68) for quick, seamless integration with your dedicated astroimaging camera, DSLR, or mirrorless camera.
Powerful in Performance, Portable in Design
This middle-ground telescope offers 1.56x the light gathering power of the FRA400 while weighing 5 lbs. less than the FRA600, making it a highly valuable tool for on-the-go astrophotographers in need of superb results. Thanks to its minimal weight of 9.03 lbs. (4 kg), the Askar FRA500 astrograph rides effortlessly atop a host of equatorial mounts on the market today, while its 16.14" (410 mm) retracted length is compact enough to carry without hassle. The included carrying handle furthers portability making this a quick, grab-and-go scope! Whether you’re in search of a manageable refractor for star parties, or planning solo imaging trips to dark skies, the Askar FRA500 is your key to outstanding astrophotos.
Rock-Solid Focusing
Fitted with a robust, 3.5” Rack & Pinion focuser, precise, smooth focus is right at your fingertips. Dual-speed in design, two separate knobs help you hone in on the details! First, find rough focus with the large knob, then utilize the smaller, 1:10 high-resolution knob for further refining. A built-in focusing scale makes it quick and easy to return to a previous point of focus, saving you time between imaging sessions. This precision machined, durable focuser is crafted with the utmost quality and provides a solid mount for your imaging equipment. Also compatible with a large majority of electronic autofocusers on the market today, you’re well equipped for automatic, hands-free focusing.
Setting You Up For Success
The FRA500 comes with several accessories to help better integrate this optical tube into your astrophotography setup. Included with the optical tube are tube rings, a retractable dew shield, a Losmandy-style dovetail plate, and a conical shaped adapter extender. This extender features M68x1, M54x0.75, M52x0.75, and M48x0.75 adapter rings, with the M48 ring housing threads for use with 2” filters. A manual is included within the box, as well as a multifunctional carrying handle to mount additional accessories if desired. On the left side of the focuser, you’ll find a standard finder base with a silver thumb screw, enabling the FRA500 to piggyback guiders, WiFi camera control devices, and other compatible accessories. A 2” visual back comes preinstalled on this FRA500, offering seamless integration with user-supplied 2” diagonals and eyepieces.
Widen Your Cosmic Horizon with this Optional Reducer!
If you’re looking to expand your field of view, check out this optional Askar 0.7x Full Frame Reducer tailored for the FRA500 astrograph! This accessory takes the original focal length of 500 mm and brings it down to 280 mm for an ultra-wide scope of vision. Capture vast portions of the night sky within a single frame, broadening your imaging opportunities. Additionally, the focal ratio is reduced from f/5.6 to f/3.9, transforming the FRA500 into a speedy, efficient system. This Askar reducer upholds the full-frame imaging capabilities of this scope by maintaining corner-to-corner sharpness. It features a back focus of 55 mm and has an M48x0.75 thread—making it perfect for 2” filter integration. Please Note: for use with this Askar FRA500 telescope, the included M86 to M68 adapter is required for attachment.
Astronomy Hub: Your one-stop-shop for Astrophotography Knowledge!
Our Gear Experts have compiled a wealth of information to help expand your astrophotography knowledge! Below you’ll find links to articles, videos and "how-to" guides. Just one more reason that our Astronomy Hub is a one-stop-shop for all your astronomy and astrophotography needs!
| The Beginner's Guide to Refractor Telescopes |
| 10 Things You Need to Know About Nebulae |
| How to Connect a Camera to a Telescope |
| No Fuss Astrophotography Telescopes for Beginners |
