Used Askar ACL 200 f/4-22 APO Astronomy Lens

The groundbreaking Askar ACL200 lens is the first camera lens specifically designed for astronomical imaging. This 200mm f/4 apochromatic lens incorporates six elements in three groups including two ED elements to minimize chromatic aberration. For astronomical applications, the Askar ACL200 outperforms traditional telephoto and zoom lenses costing far more.

With a focal ratio as fast as f/4, the manual focus Askar ACL200 lens is ideal for deep-sky wide-field astrophotography with full-frame DSLR, mirrorless, and dedicated astronomy cameras using an optional 48mm T-ring adapter. The working distance is 55mm. It can also be used with cropped-sensor cameras for which it will provide a longer effective focal length. The lens includes a manual aperture ring and precision coarse and fine manual focusing mechanisms with a distance scale that make it easy to snap stars into a tight focus. It also incorporates a filter adapter to enable the use of standard 2" astronomical filters.

For the price, this fast apochromatic lens offers excellent value and can approach the performance of telescopes that cost three or four times as much. This is especially true when matched with astronomy cameras with smaller 1" and 4/3" sensors. Cameras with larger APS-C and full-frame sensors may reveal slight aberrations at the edge of the field.

This lens is equipped with collar that allows 360° rotation for optimal framing of celestial objects. The Arca-Swiss style connection plate offers a 3/8" and 1/4" female threads for mounting to a tripod, and the plate also fits standard Vixen-style saddles. The lens weighs just 1.5kg so it's ideal for use on lightweight star tracker mounts.

With an adjustable focal ratio from f/4 to f/22, it also makes a great camera lens for wildlife, landscapes, and portraiture. The minimum focusing distance is approximately 3 meters.

Specifications:

• Focal Length: 200mm
• Minimum Aperture: f/22
• Aperture Blades: 10 pieces
• Lens Construction: Six elements (three groups of two) including two ED elements
• Closest Focusing Distance: About 3m
• Focus Mode: Manual Focus
• Focus Type: Precise focusing and rough focusing
• Micro-motion distance: 1mm
• Filter Diameter: 82mm
• Maximum Diameter and Length: About 100x195mm
• Weight: 1.5kg

Additional Info from the Manufacturer:

Askar ACL200 is an optical device especially for optimizing the quality of astrophotography, while it also caters to the needs of ground imaging. It’s compact, lightweight and easy to operate, an ideal combination of astrograph and camera lens. The optical outcome is to be dramatically improved as the distortion around the edge and achromatic aberration are greatly controlled. Askar ACL200 will bring you sharp and excellent celestial images together with a better experience of exploration.

Dual focal adjustment for astrophotography. Coarse and fine (1mm) adjustment make your focal adjustment more quick and convenient.

The world-first 200mm professional astrophotographic lens is designed with a similar appearance as an ordinary camera lens which features an integrated structure. It’s compact, light and easy to use.

Askar ACL200 is precisely designed to optimize the quality of sky imaging. This ingenious optical apparatus successfully gets rid of otherwise redundant optical accessories. You have no problem in operating ACL200 if you are familiar with ordinary cameras.

We did some modification on the old ACL200, hoping to improve our customers’ experience with it, which includes a standard Vixen dovetail base, a new-type mounting ring and two extra thumbscrews.

Compared with the old mounting ring, the new ring has an extruding stalk for the installation of the dovetail base. And the new-added dovetail base is for many purposes of attachment like finders or ASI air controllers. Furthermore, the dovetail base can also go with a dual-connection of a controller and a finder as the length of which accommodates both accessories.