Congratulations on your purchase of an Orion 80mm f/6 Triplet Refractor. Your telescope has been designed with high quality precision optics and excellent mechanical construction. The dual- speed (11:1) Crayford focuser will make getting sharp images a breeze and reduce image shift to almost zero. The three element f/6 objective lens offers excellent color correction. These instructions will help you set up and use your optical tube.
Getting Started
The 80mm Triplet comes fully assembled from the factory. The telescope’s optics have been assembled and collimated at the factory, so you should not have to make any adjustments to them.
Please keep the original shipping box. In the unlikely event you need to ship the telescope back to Orion for warranty repair service, you should use the original packaging. The box also makes a very good container for storing the telescope when it is not in use.
Optical Use
The fine optics and precision machining make the 80mm Triplet an excellent choice for astronomical and terrestrial observation. You will need to attach the 2" diagonal (included) and optional eyepiece to the back end of the telescope. The telescope will accept 2" or 1.25" accessories. Simply slide the diagonal into the open end of the telescope and insert the eyepiece into the diagonal and it is ready to show you the visual beauty of the night sky.
For terrestrial observation a correct image diagonal is recom- mended. These are typically available as 1.25" accessories only.
Use of Optional Eyepieces, Diagonal, and Finder Scope
The 80mm Triplet does not come with a finder scope or eye- pieces in order to grant the user the greatest versatility in cus- tomizing the instrument to suit their needs. However, certain rules for using accessories still apply.
Any Orion finder scope with a dovetail bracket can be used with 80mm Triplet. Simply unthread the thumbscrew on the dovetail mount and insert the assembled finder scope and dovetail bracket. Retighten the thumbscrew (Figure 1). Finder scopes that do not use a dovetail bracket will need to be attached by other means.
The 80mm Triplet can use 1.25" and 2" accessories. Please note that the telescope will not come to focus without the use of a diagonal or extension tube. To install a 1.25" diagonal, unthread the thumbscrew on the 1.25" adapter until it is flush with the interior of the adapter. Insert the diagonal or exten- sion tube and secure it with the thumbscrew. Then insert the eyepiece into the diagonal or extension tube and secure it with the thumbscrew(s).
Coarse
Focus lockfocus knob thumbscrew
11:1 fine focus knob
Figure 2: Focuser detail
Use of 2" Eyepieces and Diagonals
A feature of the 80mm Triplet is its ability to also use 2" barrel- diameter eyepieces and diagonals. At low magnifications, 2" eyepieces can give a wider field of view than standard 1.25" eyepieces. This is especially desirable for observing
To use 2" eyepieces, simply loosen the large thumbscrew on the 2" adapter (Figure 1). Once this thumbscrew is loosened, the entire back end of the focuser, including any 1.25" diago- nal and eyepiece that may be attached, comes off, exposing the 2" diameter focuser drawtube Now, insert your 2" diagonal into the drawtube and secure with the two thumbscrews loos- ened previously. Insert a 2" eyepiece into the diagonal, secure it in place with the thumbscrew on the diagonal, and you’re ready to observe.
About the 2" Dual-Speed Crayford Focuser
The Triplet 80mm comes equipped with a 2"
There is also a fine adjustment capability on this focuser. Eleven turns of the small knob protruding from the right focus knob equals one turn of the coarse adjustment knob. Once you have achieved the best possible focus on an object using the coarse adjustment knob; you can
If you find that the focus adjustment is too hard to turn or does not hold in place properly once you’ve achieved focus, you can make adjustments to the focuser tension by using the fo-
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