BRESSER Messier AR-102xs/460 Hexafoc Optical Tube - Only tube with accessories, without mounting, without tripod

BRESSER Messier AR-102xs/460 Hexafoc Optical Tube

The BRESSER Messier AR-102xs/460 is a compact 102 mm achromatic refractor with a short 460 mm focal length (f/4.5), designed as a richfield telescope - an instrument built for wide-field observation at low to moderate magnification. The combination of a generous aperture and a very short focal length produces a bright, expansive image that reveals far more of the night sky in a single view than conventional longer refractors can offer. This telescope is supplied as an optical tube assembly only, without mount or tripod.

The current version includes an objective solar filter as standard, so the telescope can be used for safe solar observation from day one - sunspot groups, partial and total solar eclipses, and planetary transits across the solar disc are all accessible without any additional purchase.

What can you observe?

The short focal length and large aperture make the AR-102xs ideally suited to extended objects that exceed the field of view of longer or smaller instruments. The Milky Way in Sagittarius reveals dozens of open clusters, nebulae and star fields simultaneously at low magnification. The Great Orion Nebula (M42), at a distance of 1,500 light years, fills the field with structured clouds of gas and the bright Trapezium stars at its core. Sweeping views of the Pleiades, the Double Cluster in Perseus and other large objects are simply spectacular.

At higher magnifications the AR-102xs handles the Moon well - tracing the terminator reveals shadow-filled craters and mountain ranges in fine contrast. Planets are observable at moderate magnifications, though a richfield refractor of this design is not primarily a planetary instrument. The maximum recommended magnification is 204x.

Optics and coatings

The 102 mm objective lens features multi-coating on all air-to-glass surfaces, reducing light loss and suppressing unwanted internal reflections for a clean, high-contrast image. The manufacturer specifies ED glass elements, which help reduce chromatic aberration - the colour fringing that is most pronounced in achromatic refractors with short focal ratios. The angular resolution of the instrument reaches 1.35 arcseconds.

2.5-inch Hexafoc focuser

One of the most notable features of the AR-102xs is its focuser. The Hexafoc drawtube offers a 2.5-inch (63.5 mm) clear inner diameter, which is among the largest available on a refractor in this price class. A wide focuser diameter ensures that even large 2-inch wide-angle eyepieces are fully illuminated without vignetting, extracting the maximum potential from the wide-field optics. The focuser accepts 2-inch (50.8 mm) accessories and includes an integrated 2-to-1.25-inch reducer with a built-in T2 thread for camera connection.

Wide-field astrophotography

The short focal length and T2 output make the AR-102xs an attractive instrument for wide-field astrophotography. With the appropriate T-ring adapter for your camera brand (T-rings are not included), the telescope becomes a 460 mm f/4.5 photographic lens. Large nebula complexes, open clusters and sweeping sections of the Milky Way are ideal targets for short-exposure imaging sessions.

Mounting and portability

The optical tube is fitted with a universal 44 mm dovetail bar with a stainless steel clamping surface, compatible with the GP (Vixen), EQ5 and LXD75 standards. It fits the vast majority of mid-range equatorial mounts suitable for a richfield refractor of this aperture. The tube weighs 2.8 kg with accessories and is compact enough for field use or travel.

Package contents

• AR-102xs/460 optical tube
• 26 mm Super Plössl eyepiece 1.25"
• 1.25" star diagonal
• 2" to 1.25" reducer with integrated T2 thread
• 44 mm dovetail bar (GP/EQ5/LXD75)
• 6x30 straight-through finderscope
• Objective solar filter
• Rotating star chart
• Stellarium software (download)

Technical specifications