Bresser AC 90/900 Messier Refractor OTA

Description

Favoring contrast over field width, the Bresser AC 90/900 Messier Refractor OTA sits in genuine long-focus territory at f/10, delivering lunar and planetary contrast the wide fields of a shorter tube can’t match. This version ships as a bare optical tube, no mount included, riding on a universal Vixen-style dovetail.

At 3.2kg, this tube pairs with most mounts already rated for a similar aperture refractor. Its 1.25-inch zenith mirror keeps the accessory kit simple compared to the 2-inch format on the mounted versions in this line — worth noting if you’re planning to add wider eyepieces later, since upgrading to a 2-inch format down the road would mean replacing this diagonal rather than just adding an eyepiece.

Key Features of Bresser AC 90/900 Messier Refractor OTA

A 90mm achromatic objective at f/10 resolves down to 1.28 arcseconds, reaching a limiting magnitude of 11.6 for lunar and planetary detail that rewards patient viewing.

• 90mm aperture at f/10 favors lunar and planetary contrast over wide framing
• 2.5-inch Hexafoc heavy-duty focuser holds eyepieces steady at higher power
• Integrated piggyback camera mount lets this tube ride alongside a second scope
• 6×30 optical finder scope speeds up target acquisition before switching eyepieces
• Included 26mm Super Plossl eyepiece delivers 34x magnification right out of the box
• Magnification range from 13x to 180x reaches genuine planetary detail
• Long focal length suits an observer prioritizing detail over sweeping star fields

What Sets the AR-90L/900 OTA Apart

Every mounted version of this same 90mm tube shares identical optics — this OTA-only version suits buyers who already own a mount and don’t need the 2-inch eyepiece format the EXOS-bundled versions add.

Applications & Use Cases

Built as a standalone long-focus optical tube, this telescope suits sharp planetary tracking, high-contrast lunar inspection, and traditional visual observation for an observer building around existing gear.

• Observers who already own a compatible mount
• Anyone wanting a dedicated long-focus planetary tube for an existing rig
• Buyers who don’t need the 2-inch eyepiece format the bundled versions add

Bresser Warranty & Support

The AR-90L/900 OTA carries a 2-Year Factory Warranty covering manufacturing defects, handled directly through Bresser’s support channel.