Askar FRA600 108 mm Quintuplet APO Astrograph
A Big Aperture Flat-Field Refractive Astrograph from Askar - The 108 mm FRA600!
The FRA600 APO refractor is one of the premier scopes in the Flat-Field Refractive Astrograph line from Askar, with a 600 mm focal length and 108 mm aperture. The FRA600 has 1.4x more light gathering power than the FRA500. With the same quick f/5.6 focal ratio of the other FRA refractors, this telescope is an excellent choice for astrophotographers!
While not quite as light as Askar's other offerings in this lineup, the FRA600 108 mm Quintuplet APO Astrograph still comes in at a svelte 14 lbs. This makes it a possible contender for heavier imaging setups looking to push the 30 lbs capacity class mounts, and a perfect pairing for heavier capacity mounts!
Packed into this telescope are a total of five optical elements arranged in a Petzval design, which give the FRA600 108 mm Quintuplet APO Astrograph a large flat field without the need for a separate flattener. The image circle provided by this telescope is an impressive 66 mm, allowing the FRA600 to easily accommodate full-frame sensor cameras. This design also makes backfocus easy meaning you can focus gathering light, not gathering spacers. Rounding out this design is the inclusion of two ED elements, which result in superb chromatic aberration control.
Everything Needed to Integrate the FRA600 Into Your Astrophotography Setup
The FRA600 108 mm Quintuplet APO Astrograph comes with the essential items you'll need to get this telescope integrated into your setup! A set of tube rings, with a hex key wrench for adjustments, and convenient carry handle come in the box, making it easy to transport this scope safely. Also included is a Losmandy style dovetail plate for connecting this to your mount. Last but not least, the FRA600 includes a conical extender and set of adapters for attaching a multitude of optical train components.
Novel Quintuplet Optical Design
"Astrograph" refers to a telescope designed to excel in astrophotography, and the Askar FRA600 certainly lives up to that name with its excellent optics! With a 108 mm aperture, this telescope combines 5 elements in a 3+2 arrangement with two ED glass elements, resulting in a flat field and excellent apochromatic performance without additional corrective accessories. Utilizing a Petzval design, the FRA600 also provide a hassle-free backfocus experience. No need for complex calculations here. As long as you can reach focus you'll have a sharp, flat, image!
Several Helpful Accessories Included
A number of helpful accessories make the FRA600 easy to add into your imaging setup. The included tube rings have attachment points on three sides, giving you the versatility to attach the handle and other accessories in a wide variety of configurations. Also in the box is a conical extender and M90x1, M68x1, M54x0.75, and M48x0.75 adapter rings for connecting cameras and other optical train accessories. Lastly, a manual and hex key wrench are provided to assist with the setup of your FRA600 refractor.
Recommended: Askar f/3.9 Full-Frame Reducer (Sold Separately)
This full-frame reducer from Askar (sold separately) allows you to push the speed of your FRA600 even further. This 0.7X reducer brings the focal ratio to f/3.9 and shortens the focal length to 420 mm, giving you the power to image larger, fainter, targets with the FRA600 APO refractor.
