Askar 106 mm f/4.8 Quintuplet Flatfield Apochromat with optical test from TS

Askar 106 mm f/4.8 Quintuplet Astrograph

This high-quality quintuplet air-spaced SD glass Petzval astrograph is very well suited for astrophotography of larger areas with full-frame cameras.

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 1.7 µm, and the star point at the corner is less than 2.2 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 and giving very good results up to 55 mm 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
Large, rigid 2.8-inch dual-speed rack-and-pinion focuser which can be compatible with most motorized focusers on the market. The focusing travel is 30 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 SQA106 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 SQA106 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.

This is how we hand over the apo to the stargazer:
Every single APO is checked in our technical department before it is put into storage in order to guarantee consistently high product quality.

The mechanics are tested and the focuser is optimally adjusted.

The lens is cosmetically checked and cleaned. We also check that all counter screws are correctly tightened. These often loosen during transportation.

The optics are collimated and the result is checked on the optical bench. The telescope is given a serial number.

An optical test is carried out, which is enclosed with the telescope (star images and ronchi image on the optical bench in autocollimation).

Only then are the telescopes handed over to the warehouse and prepared for dispatch.

Safety informations: PDF Download