Corvane Bramble 114 Dobsonian, with Dobsonian base

Specifications

Description

The Bramble 114 is a Newtonian reflector mounted on a Dobsonian rocker base. Its 114 mm parabolic primary mirror has a focal length of 684 mm, which gives a focal ratio of f/6. At that ratio, a 20 mm eyepiece gives about 34 times magnification, and a 25 mm eyepiece gives about 27 times, a range that suits star clusters, bright nebulae, the Moon, and the planets. The mirror carries an aluminum coating with a protective overcoat, which helps it keep its reflectivity between recoatings.

The rocker base uses a plywood box with a Teflon-faced altitude bearing and a sliding azimuth surface, so you can move the tube smoothly by hand without a tripod. The base folds into two pieces for storage and transport. The 2 in single-speed Crayford-style focuser holds a star diagonal and a heavy eyepiece steadily, and the 6x30 finder scope gives a wide view for locating targets before you center them in the main eyepiece. Collimation is done with adjustment screws on the secondary holder and the primary cell, which keeps the optics aligned after transport.

Because the tube is open at the top and sits on a low base, the 114 mm mirror reaches the outdoor air temperature within roughly one hour, which reduces tube currents when you start observing. The tube weighs 6.4 kg, and the base adds further weight, so the whole instrument is best set up in one place rather than carried often. Typical targets include the Orion Nebula, the Ring Nebula, the Andromeda Galaxy, and the globular clusters of Hercules, which show resolved stars under dark skies. On the Moon and planets, the mirror shows crater detail, the belts of Jupiter, and the Cassini Division of Saturn's rings when seeing is steady.

About this configuration

This listing covers one specific configuration of the Corvane Bramble 114 Dobsonian, defined by its bundle, finish, accessory kit, and edition year. The Dobsonian rocker base keeps the telescope low and stable, and you aim it by pushing the tube gently by hand. The base and the tube separate for transport, which makes the telescope easier to carry out of the house in two trips. Matte black paint gives the telescope a low-key look, although a dark tube is harder to find on a moonless night.

The starter kit adds two eyepieces and a Barlow lens, which gives you four magnifications from three pieces. The 2023 edition uses the same optical design as later years, with small differences in fittings and labels. Check the specifications table for the optical figures, since they stay the same across every configuration of the Bramble line.

What's in the box

• Optical tube with primary and secondary mirrors
• Rocker base in two sections
• 2 in single-speed focuser
• 6x30 optical finder scope with bracket
• Collimation tool
• Dust caps for focuser and tube
• Dobsonian rocker base with altitude bearings
• 25 mm and 10 mm eyepieces (1.25 in)
• 2x Barlow lens (1.25 in)

Compatibility notes

• Accepts 2 in eyepieces and 2 in star diagonals directly.
• Accepts 1.25 in eyepieces through the supplied 1.25 in adapter.
• The rocker base works on a table or a sturdy stand for low-profile observing.