High-quality quintuplet air-spaced SD glass Petzval Astrograph SQA85

Superior star point performance

Quintuplet air-spaced lens design, including 2 pieces of SD glass. The central star point has an RMS radius of less than 1.6 µm, and the star point at the corner is less than 2.5 µm, showing a super-fine star point. It also has excellent full-field illumination and MTF data.

Petzval structure

Integrated self-flattened design, supporting a 44 mm full-frame image circle, no need for additional flatteners, and no need for additional calculation of the back focus. Between 40 mm and 70 mm connection distance, users can directly use it for shooting after the OTA is in focus.

Retractable dew shield

The dew shield is a retractable design that can be pulled out when used. It protects the lens from the impact of external and internal light and protects the lens itself.

Large, rigid dual-speed focuser

Dual-speed rack-and-pinion large 2.8-inch rigid focuser, which can be compatible with most motorized focusers on the market. The focusing travel is 32 mm, and the focuser tube is engraved with high-precision scales. The entire focuser barrel is CNC machined with an anti-reflective internal design and matting paint, providing extra measures to eliminate stray light.

360° rotator

The rear of the focuser is equipped with a 360° high-precision rotator with a precision scale to allow the user to adjust and save the angle of rotation. It is also equipped with an enlarged locking screw for easy locking even under high loads.

Rear-end adapters

The end of the SQA85 is equipped with a variety of adapters, all of which are toothed and ribbed, making it easy to rotate manually without slipping. The adapters are available in sizes M68, M54, and M48 and can be used to attach various accessories, such as full-frame cameras.

Integrated tube ring

The tube ring features a hollow design in the middle to reduce overall weight.

Enlarged hand screws allow users to open and close the tube ring without additional tools.

There are 6 M4 and M6 threaded holes on both sides of the tube ring, which are convenient for installing the base or dovetail plate and connecting different accessories. You can even set up another set of OTA for shooting.

The handle on the top of the tube ring is slotted with a multifunctional finder base, which can be used to install astronomical accessories.

Finder bases

On both sides of the focuser, there are two finder bases, which not only eliminate the need for disassembling when changing the position of the finder scope but also provide additional mounting positions for other astronomical accessories.

High-quality machining

The entire SQA85 tube is crafted using high-quality CNC machining with anodized and surface spray paint treatments. The top of the handle and the focuser are all designed with exclusive nameplates, demonstrating high-end quality.

Features

• Aperture: 85 mm
• Focal length: 408 mm
• Focal ratio: f/4.8
• Objective lens: Quintuplet Petzval apo (including two pieces of SD glass), self-flattening
• Format specifications: full-frame
• Star point radius:    less than 1.6 µm rms at the center, less than 2.5 µm rms at the corner
• Focuser: 2.8-inch dual-speed focuser
• Focusing travel: 32 mm
• Rotator: 360°, lockable
• Dew shield: Retractable
• Total length: 403 mm when the dew shield is contracted, 439 mm when the dew shield is stretched
• Rear-end thread type: M48x0.75, M54x0.75 und M68x1 via adapter
• Rear-end connection distance: Supports 40-70 mm range (recommended connection length is 55 mm)
• Finder bases on the focuser: 2
• Tube ring: With additional finder base
• Mount connection: Vixen-style dovetail bar, length 290 mm
• Tube length: 408 mm with covers
• Tube height with tube ring and dovetail bar: 145 mm
• Dew shield diameter: 111 mm
• OTA weight: 3.64 kg