The Askar SQA106 refractor astrograph features a five-lens internal design that corrects incoming light to minimize coma, field curvature, and other aberrations, resulting in clear images with precise star pointAskar - SQA106 Quintuplet Refractors. The Petzval lens system simplifies camera attachment and provides a flat field suitable for full-frame cameras without requiring backfocus calculations. With a fast f/4.8 focal ratio, a dual-speed focuser for precise adjustments, and a range of included accessories, the Askar SQA106 is a practical choice for enhancing your astrophotography setup.

The Askar SQA106 refractor features a 106 mm aperture, enabling effective light collection for capturing detailed structures in galaxies, nebulae, and other celestial objects. With a 509 mm focal length, it offers excellent imaging performance. Constructed with precision CNC machining, the refractor showcases the signature gray finish of the SQA line and an anodized coating for durability and a polished appearance. The package includes multiple adapters, a Losmandy-style dovetail, a tube ring, and additional accessories, providing the tools needed for advanced astrophotography.

• Optical Design for Astrophotography: The Askar SQA106 features a 106 mm aperture and a 509 mm focal length, offering strong light collection and sharp imaging of celestial objects like galaxies and nebulae.
• Advanced Lens System: A five-lens Petzval design minimizes optical aberrations, such as coma and field curvature, ensuring clarity and compatibility with full-frame cameras.
• Ease of Use: The refractor eliminates the need for backfocus calculations and simplifies camera attachment, enhancing user convenience.
• Precision Construction: Built with high-quality CNC machining, the refractor features a durable anodized finish in the signature gray of the SQA line.
• Comprehensive Accessories: The package includes essential items like a Losmandy-style dovetail, tube ring, and multiple adapters, supporting a complete astrophotography setup.

The Askar SQA106 is a versatile astrophotography refractor designed to deliver exceptional optical performance. Its quintuplet design features five internal lens elements, including two made from high-quality super-low dispersion (SD) glass. This advanced configuration ensures precise correction of incoming light, producing high-contrast images free from aberrations. With a built-in flat field design, the SQA106 provides sharp, in-focus star points across the entire image plane, eliminating the need for a separate field flattener.  

The telescope supports a 55 mm image circle, accommodating large imaging sensors and offering flexibility for various astrophotography setups. Its simplified design removes the need for exact backspacing adjustments—if your imaging train reaches focus, the results will be sharp and consistent. Built for reliability and ease of use, the Askar SQA106 combines exceptional optics, a high-precision focuser, and a range of included accessories, making it an excellent choice for capturing celestial detail.  

To validate the optical precision of the SQA106, Askar has conducted rigorous testing, with results presented in detailed graphical analyses that highlight the telescope’s performance. One key evaluation is the Modulation Transfer Function (MTF) graph, which quantifies the telescope's ability to transmit light through its optical system. The vertical axis of the graph represents the MTF value, where 1.0 signifies perfect light transmission, while the horizontal axis corresponds to the distance from the center to the edge of the frame. When tested at low spatial frequencies (represented by blue lines), the SQA106 achieves MTF values exceeding 0.9, demonstrating its ability to deliver exceptional resolution and sharpness across the image field.  

Another critical test involves the Relative Illumination (RI) graph, which measures the evenness of illumination from the center to the edges of the frame. The SQA106 maintains over 90% illumination across a 44 mm imaging field and 75% illumination over a 55 mm imaging field, ensuring minimal vignetting and allowing for detailed imaging across large sensors. These results highlight the telescope's capability to provide consistent brightness and clarity, making it highly effective for capturing intricate celestial details.  

These tests underscore the precision and reliability of the SQA106, ensuring that its optical system meets the exacting standards required for advanced astrophotography.