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Coulter Odyssey I 13.1 f/4.5 matching mirrors 1986 Sold!

Price - $274.00

Ad Number: 183770

Posted: 18 Sep 2019

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This here is a 1986 Coulter Odyssey I matching mirrors kit for a 13.1-inch f/4.5. This will come with the primary, matching secondary, and secondary stalk mounting. If you are careful and take a little time, you can safely remove the secondary from the stalk housing and place it in a true 4-vane spider assembly; a BIG improvement.

Primary design: parabolic figure on plate glass
Primary width: 13.1-inches
Primary focal length: 60-inches
Primary thickness: 1.09-inches
Primary weight: 10 pounds 13 ounces
Secondary design: elliptical flat on pyrex glass
Secondary minor axis: 2.61-inches
Secondary major axis: 3.68-inches
Secondary thickness: 0.62-inches
Secondary weight: 9 ounces (does not include stalk)

This is slightly less in thickness over other 13.1s I've had in the past; though it is not the thinnest. That belonged to a 1988 13.1 that was only 1.02-inches.

The primary mirror is in excellent condition. Aside from one chip, which is near the underside cut (rear face), the others are original from the factory that ground the mirror. Those chips have the baked-on sparkle finish, and proves those, along with the underside cut, was stock from Coulter Optical's technicians. The black inked characters on the rim of the mirror are also stock from Coulter. The only modification ever done to it is the red dot I placed in the middle, which can be removed. It is accurately centered.
The reflective coating on the primary is in excellent condition with hairlines, but NO pitting issues or any scratches to the figure. NO need to recoat for sure.

The secondary mirror is in very excellent condition, including the reflective coat.

Optical performance on this 13.1 is GREAT for deep sky cruising of galaxies and nebulae of all sorts, and very good at resolving globular clusters. It is not a planetary reflector. Do keep in mind that this mirror did not have the ability for its secondary to be collimated, so some, but not a lot, of the lack of tight resolution can be attributed to this design "flaw".

Price doesn't include shipping. Will ship to anyone on Earth.


  • Condition excellent
  • Location Veradale, WA

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