Askar SQA55 Quintuplet Astrograph

The SQA55 is a high-performance OTA with a 55mm aperture, a 264mm focal length, and a native focal ratio of F4.8. Designed as a quintuplet air-spaced SD glass Petzval astrograph, it excels in both astrophotography and everyday photography.

Askar's SQA55 offers remarkable star point performance, thanks to its quintuplet air-spaced design, which incorporates one piece of SD glass and one piece of ED glass, supporting 44mm full-frame imaging. Its self-flattened design eliminates the need for calculating specific back focus, allowing for direct shooting after focusing with a connection distance between 50mm and 60mm (recommended length is 55mm).

Askar SQA55 Quintuplet Astrograph

The interior of the lens tube features matte lines and an overall matte paint coating to reduce stray light. The lens hood can be reversed and stored on the lens barrel when not in use, minimizing overall volume. When needed, it can easily be attached to the lens.

The front of the lens has an M67 filter thread, facilitating the use of camera filters for daily photography. The rear-end includes an M48 adapter with a built-in 2" filter thread for direct connection.

With an aperture range from F22 to F4.8, the SQA55 includes a graded adjustment ring and a labeled scale on the lens tube to prevent accidental adjustments and maintain the set parameters.

The handle includes a multifunctional finder scope base slot for mounting various astronomical accessories. It features a quick-release design, allowing for tool-free removal and installation. The bottom bracket has 1/4 and 3/8 screw holes for tripod attachment.

The standard Vixen-style 200mm dovetail plate at the bottom is equipped with hand screws and a quick-release knob, making it easy to disassemble and assemble without additional tools. The SQA55's dual-speed focuser offers both fine and coarse adjustments, which can be independently controlled. The fine adjustment has a central indicator point, a focusing travel of ±1mm, and a locking screw. The coarse adjustment is marked with a reference scale for focusing distance in both imperial and metric units. For daily photography, focusing can be adjusted using the scale. The coarse adjustment handwheel includes MXL-type timing teeth for use with a timing belt to mount an electronic focuser.

For astrophotography, the coarse adjustment can be set to the infinity mark, with some leeway beyond it. A locking screw allows for individual adjustments.

The lens tube has four multifunctional quick-release bases at the rear for connecting various accessories for photography and astrophotography. Both the SQA55 lens tube and the 360° rotator have independent locking screws. The entire body can be rotated for daily shooting, while the high-precision rotator can be independently adjusted for astrophotography, with an engraved scale for easy angle adjustments.

Askar SQA55 specs

• Aperture: 55mm
• Focal length: 264mm
• Focal ratio: F4.8
• Objective lens: Quintuplet air-spaced Petzval APO
• Total length: 316mm (including dew shield); 244mm (without dew shield)
• OTA weight: 1.84kg
• Total weight: 2.18kg
• Rear-end adapter: M48*0.75 (with M48×0.75 filter thread)
• Accessories: SQA55 OTA, Military-grade waterproof hand-carrying case, Inspection list, Manual
• Built-in 2-inch filter adapter: M59×0.75 | M48×0.75