Aurel Meridian 305 Dobsonian, with Dobsonian base

Specifications

Description

The Meridian 305 is a 12-inch Newtonian reflector with a 305 mm parabolic mirror and a 1,500 mm focal length, at f/4.9. It is designed for observers who want to see faint galaxies, small planetary nebulae, and globular clusters in detail.

A 305 mm mirror gathers about 19 times as much light as a 70 mm refractor and about 2.3 times as much as a 203 mm mirror. Under dark skies that opens up thousands of galaxies, including many in the NGC catalog that smaller telescopes show only as faint smudges. Bright galaxies such as M51 and M101 show spiral arms, and the Veil Nebula shows its filaments with a narrowband filter.

The tube uses a truss-free solid design with an internal light baffle, which keeps stray light out without a shroud. Three cooling fans move air across the primary mirror, and the mirror cell has tool-free collimation knobs. At f/4.9, collimation matters, so a laser collimator or a Cheshire tool is a good addition.

The 1,500 mm focal length reaches 250x with a 6 mm eyepiece. On nights of steady air, that shows fine detail on Jupiter and Saturn and splits close double stars. The 2 in dual-speed Crayford focuser handles heavy wide-field eyepieces and has a 10:1 fine-focus knob.

The tube weighs 21.5 kg and the base about 18 kg. Most people can carry each part a short distance, but stairs and long walks make a hand truck or a wheeled base worth considering. The eyepiece at the zenith sits about 1.5 m above the ground, which suits a standing adult or a tall observing chair.

About this configuration

The Aurel Meridian 305 Dobsonian is offered in several configurations, and the notes below describe what this particular combination adds or changes. The Dobsonian rocker base keeps the telescope low and stable, and you aim it by pushing the tube gently by hand. A Dobsonian base needs no alignment, so you can set it on level ground and start observing within a few minutes. The matte black finish hides scuffs and keeps reflections from porch lights and streetlights to a minimum.

This configuration comes without extra accessories, so budget for at least one more eyepiece if you are starting out. The 2023 edition uses the same optical design as later years, with small differences in fittings and labels. If you plan to add accessories later, compare the compatibility notes with the parts you already own before choosing a configuration.

What's in the box

• Optical tube with 305 mm parabolic primary mirror
• Three primary mirror cooling fans with battery holder
• 8x50 right-angle correct-image finder with bracket
• 2 in to 1.25 in adapter
• Collimation cap
• Carry handles on the tube
• Dobsonian rocker base with altitude bearings

Compatibility notes

• Accepts 2 in and 1.25 in eyepieces, filters, and coma correctors.
• The tube fits the matching Dobsonian base; the tube-only version needs a large equatorial mount rated for at least 35 kg.
• Push-to encoders for 12-inch Dobsonian bases fit the altitude and azimuth bearings.