Askar "SQA130 Telescope Tube" Launched: A 130mm Aperture, 5-Group 5-Element (with 2 SD Glass Elements) Ultra-High Resolution Petzval-Type Astrograph

Sightron Japan Co., Ltd. (Headquarters: Shinjuku-ku, Tokyo; Representative Director: Akira Watanabe) will launch the "SQA130 Telescope Tube," a large-aperture astrograph from Jiaxing Ruixing Optical Instrument's astronomical telescope brand Askar, boasting exceptional optical performance and beautiful star images, on March 27, 2026.

Product Features

Uncompromising Optical Performance: 5-Group, 5-Element Air-Spaced Petzval Design

・ The "SQA130" is a new generation astrograph with a 130mm objective lens aperture and a bright focal length of 624mm (f/4.8 aperture ratio).

・ It adopts a 5-group, 5-element lens configuration, with two of these lenses luxuriously utilizing SD glass (Special Low Dispersion glass). This corrects various aberrations to the extreme, producing extremely sharp and high-contrast images across the entire field of view.

・ Thanks to the Petzval structure, a flat image field can be obtained with the telescope tube alone. With all lenses fixed in their proper positions, focusing can be achieved within a range of 46mm to 76mm (55mm recommended) without worrying about troublesome backfocus calculations.

Image Circle that Easily Covers Full-Frame and Ultimate Star Images

・ The image circle supports medium format (φ55mm), not only covering the vast sensor area of full-frame (φ44mm) but also ensuring abundant peripheral illumination right up to the very edges. Peripheral illumination reaches approximately 85% at the outermost edge of medium format and approximately 95% at the outermost edge of full-frame.

・ It achieves astonishing star images with an RMS spot radius of less than 2μm at the center and less than 2.4μm even at the periphery of full-frame. This minimizes vignetting and star image distortion, significantly reducing the burden of image processing.

Robust yet Lightweight Mechanical Design for Astrophotography Enthusiasts

・ The tube rings adopt a hollow design (lightening process) meticulously CNC-machined from aircraft-grade aluminum. This achieves overall system weight reduction while maintaining sufficient high rigidity. Large thumb screws allow for opening/closing and front/back sliding of the telescope tube without tools, even when wearing gloves in cold environments.

・ The tube rings are equipped with a total of six M4/M6 screw holes on both sides, flexibly accommodating the attachment of various accessories such as controllers.

・ A 300mm long wide dovetail plate is standardly included at the bottom of the telescope tube, for large...