The Askar FRA500 has benefited from the design of the FRA series. It offers a quintuplet air-spaced APO optical structure with a Petzval lens combination of a “three plus two” design. What this means is the front lens group consists of three of the lenses; tow of which are comprised of a two-piece ED glass which excels at correcting aberrations.

The rear set of lenses is made up of two lenses that are separated by a small space that offers an acute sharpness across the image you produce from edge to edge, offering an effective flat field. This will give you pinpoint, crisp stars to the edge of your field of view.

The FRA500 offers a superior 55mm imaging circle over the standard 44mm full frame imaging circle that other telescopes tend to offer. Combined with back focus design that frees the user from having to make complicated back focus calculations; what you need to attain focus with most imaging devices is with the Askar FRA500 astrograph so you can spend more time imaging and less time fumbling around with adapters.

• Aperture size：90mm
• Focal length：500mm
• Focal ratio：f/5.6
• Objective lens：Quintuplet air-spaced APO (including two ED glass)
• Image circle：55mm
• Back focus：158mm（from base of M48×0.75 thread on the conical extender to focal plane）
  • 85mm（from base of M86×1 thread on the rotator to focal plane）
• Total length：452mm（410mm when the dew shield is contracted）
• Net weight：4.1kg
• Gross weight：5.2kg
• Rear-end thread type：M86×1
• Conical adapter：M48×0.75
• Package items：an FRA500 OTA, a pair of tube rings, a handle, an Askar Losmandy dovetail plate, a conical extender, a manual

The Askar FRA500 is CNC machined with an attractive and decorative paint design making it pleasing to the eye and a practical layout of the components for ease of use. It features a retractable dew shield; when extended, the astrograph is only 452mm in length, when retracted; the FRA500 is only 410mm long.

At the rear of the FRA500 is the 3.5” focuser that features a dual-speed twin knobs; one for coarse adjustment and the other for1:10 fine adjustment which is handy for both visual observation as well as astrophotography.

The Askar FRA500 has a smooth coating with an even finish. The focuser also features a standard finder base; sporting a silver screw so you can mount guiders, finders and any other accessories you may wish to use.

 The Askar Quintuplet APO Astrograph also comes with tube rings with an attached carry handle on top which sports a M6 tapped hole to add accessories if needed and on the bottom, a 300mm Losmandy style dovetail plate.

What makes the Askar FRA500 a perfect grab and go scope is it’s length of 410mm and its weight of 4Kg’s so if you have a long way to travel, its easier to use this compact astrograph for your astronomy needs.

Warranty. manufacturer 1 year