A quintuplet petzval astrograph from Askar

In February 2025, Askar introduced the SQA106, a telescope designed specifically for astrophotography enthusiasts.  This quintuplet Petzval refractor combines advanced optics with user-friendly features, making it a valuable tool for capturing the night sky.

Optical design and performance

The SQA106 features a 106mm aperture and a 509mm focal length, resulting in a fast focal ratio of f/4.8.  Its optical system comprises five elements, including two Super Low Dispersion (SD) glass components, arranged in a Petzval configuration.  This design effectively minimizes chromatic aberration and field curvature, ensuring sharp and clear images across the entire field of view.

The telescope supports a 55mm image circle, accommodating both full-frame and medium-format sensors.  This allows for wide-field imaging without the need for additional field flatteners.  The central star point has an RMS radius of less than 1.7 µm, and the corner star point is under 2.2 µm, indicating excellent sharpness throughout the image.

Mechanical features

The SQA106 is constructed with precision CNC machining, providing a robust and durable build.  It includes a 2.8-inch dual-speed rack-and-pinion focuser, compatible with most motorized focusing systems, allowing for precise adjustments during imaging sessions.

A 360° rotator with a precision scale is integrated into the focuser, facilitating easy framing adjustments.  The telescope also features a retractable dew shield to protect the optics from stray light and dew, enhancing image quality during observations.

Mounting and compatibility

The SQA106 comes equipped with a 300mm Losmandy-style dovetail plate, ensuring compatibility with a wide range of equatorial mounts.  The integrated tube ring has a hollow design to reduce weight and includes multiple M4 and M6 threaded holes for attaching accessories.  A multifunctional handle with a slotted finder base is also provided, offering additional mounting options.

The telescope supports a back focus range of 48mm to 78mm, with an optimal distance of 55mm.  This flexibility accommodates various camera setups and accessories.  Included are M48, M54, and M68 adapters, allowing for straightforward connections to different imaging equipment.

Key features

Here are some of the key features of Askar SQA106:

• Native flat-field performance with no need for an external field flattener
• Internal Petzval design ensures sharp stars from center to edge
• Fully illuminated 55 mm image circle for full-frame compatibility
• Excellent correction of chromatic aberration and field curvature
• Compatible with a wide range of astrophotography accessories
• Dual finder bases and multifunctional handle for flexible mounting
• Precision rotator with scale for accurate image framing

Technical specifications

• Aperture: 106mm
• Focal length: 509mm
• Focal ratio: f/4.8
• Optical design: Quintuplet Petzval with 2 SD glass elements
• Tube length: 516 mm (retracted), 586mm (extended)
• Weight: 5.82 kg (optical tube only), 8.12 kg (with accessories)
• Focuser: 2.8″ dual-speed rack and pinion with 1:10 micro-reduction
• Rotator: 360° with lock screw and precision scale
• Back focus: 48mm–78mm (optimal at 55mm)
• Accessories: M48, M54, M68 adapters, finder bases, Oxford cloth case

Price and availability

The Askar SQA106 is available to order from the official website and other retailers for $3,395.

The Askar SQA106 stands out as a high-performance astrograph, combining advanced optical design with practical features tailored for astrophotography.  Its quintuplet Petzval configuration ensures sharp, aberration-free images across a wide field, while its mechanical components provide stability and ease of use.  Whether you’re capturing expansive nebulae or detailed galaxy shots, the SQA106 offers the tools needed for exceptional astrophotography experiences.

Clear skies!