Coulter Optical Co.

Coulter Optical entered the astronomy world in 1968 by producing low cost, reasonable quality parabolic mirrors. Later they became renowned for their inexpensive but usable Dobsonian style reflectors. The company folded late in 1995, not long after the death of the creator of the company, but in 1997, Murnaghan Instruments once again made the Coulter line of telescopes available at somewhat lower quality. In 2001 Murnaghan brought the line to the end for the final time.

Coulter's first complete telescope was the CT-100, a 4 " f/3.5 reflector with open tube, introduced in 1978. This was designed especially as a light-weight travel telescope. The optical tube was supplied with a 1 " helical focuser, 3 eyepieces, and a case and weighed only 8.5 pounds. In 1979 it was made available with an equatorial mount in larger case with the system weighing 25 pounds.
CT 100
Original Odyssey Compact 17.5" Odyssey II
In 1980 Coulter became the first manufacturer to capitalize and market the "Dobsonian" telescope. Odyssey 1 was a 13.1" f/4.5 instrument with standard 1 " focuser, that allowed true deep sky viewing for a remarkably low price. The first tubes had a large box shape at their lower extremity, with a trap door where the mirror sat in a sling. This meant that the mirror had to be removed each time you moved the telescope. It also resulted in a telescope that weighed 120 pounds. Later the design was changed to the more common tube we see today with a particle board push-pull mirror cell, and the mirror thickness was reduced from the standard 1:6 ratio to 1:13. This resulted in a savings of almost 20 pounds and resulted in a more portable telescope. All Odyssey telescopes were constructed of painted Sonotube placed on painted particle board boxes. The original Odyssey became a hit almost immediately, and other telescopes were announced. One was the Odyssey Compact. This was a 10.1" f/4.5 telescope. Another was the Odyssey 2 or II, which had a 17.5" f/4.5 optical tube. All of these telescopes made use of a very simple 1 " slide focusing tube in a sleeve with adjustable tension. All of these were initially produced with the box at the lower end of the tube, but later redesigned as a standard tube.
In 1984 the truely compact Odyssey 8 was added. This made use of an 8" f/4.5 optical tube on small but sturdy Dobsonian mount. This was supplemented about a decade later with the Odyssey 8" f/7 mounted on the same cradle. This spurred the 1995 announcement of the Odyssey 8 Combo. This was a unique combination of two optical tube assemblies, one Dobsonian mount and one eyepiece. Either tube could be placed on the one mount to provide either wide field views or greater magnification. Both tubes had 1 " helical focusers.
Shortly before the company's demise a new Odyssey 2 was made available, not to be confused with the Odyssey 2 above. This was a 16" f/4.5 telescope with a standard 1 " helical focuser and eyepiece.

© 2001 - 2004 - Robert A. Pollock
Page Revised: May 1, 2004