Operating the EON Refractor | Orion #9781 EON 72MM guide

3.Secure the barrel in place by firmly tightening the thumbscrew on the 1.25" eyepiece adapter.

To attach a 2" diagonal or extension tube to your telescope:

1.Loosen the thumbscrew on the Crayford focuser’s 2" eyepiece holder and remove the 1.25" eyepiece adapter.

2.Insert the barrel of your diagonal or extension tube into the 2" eyepiece holder.

3.Secure the barrel in place by firmly tightening the thumbscrew.

1.25" Eyepiece adapter thumbscrew

2" Eyepiece holder thumbscrew

To insert a finder scope onto your EON refractor, slide the finder scope bracket into the finder scope dovetail base and secure it in place by tightening the thumbscrew(s) on the dove- tail base (Figure 6).

Brass compression ring

2" Eyepiece holder

1.25" Eyepiece adapter

Figure 4. The EON refractors accept both 1.25" and 2” accessories. The brass compression rings in the 1.25" eyepiece adapter and 2" eyepiece holder ensure a secure fit without marking up the barrel of your accessory.

Finder Scope Compatibility

The included finder scope dovetail base on the EON 80mm and 120mm refractors are ready to accept any Orion finder scope. The EON 72mm does not include a finder scope dovetail base; however, it is available optionally from Orion and directly fits the holes in the EON 72mm (Figure 5).

Holes for optional finder scope dovetail base

Figure 5. The EON 72mm is compatible with the Orion finder scope dovetail base.

Figure 6. Slide the finder scope bracket into the finder scope dovetail base and secure the locking thumbscrew(s).

Operating the EON

Refractor

Now that you have become familiar with the different fea- tures and functions of your EON refractor, you are ready to begin using your new telescope outside under a starry night. The EON refractors are essentially ready to begin observing with immediately. There is a small period of time where the internal temperature of the telescope must match the out- side temperature to obtain the best image quality. This time period is nearly nominal, taking only a few minutes. Typically, the EON will have reached outside temperature by the time the telescope is setup.

Mounting block

Dovetail plate 1/4"-20 threads

Figure 7. The EON 72mm and 80mm have a built-in mounting block ready to connect to a sturdy camera tripod or telescope mount.

#9781 EON 72MM specifications

The Orion #9781 EON 72MM is a premium refractor telescope designed for both amateur astronomers and seasoned stargazers. Renowned for its impressive optical performance and robust build quality, the EON 72MM combines advanced technologies with user-friendly features, making it an excellent choice for those looking to explore the night sky in detail.

One of the standout features of the EON 72MM is its high-quality 72mm apochromatic objective lens. This lens is engineered with exceptional glass quality that minimizes chromatic aberration and maximizes color correction. As a result, users can expect crisp, clear images with true-to-life color representation, allowing for stunning views of celestial objects such as planets, nebulae, and star clusters.

The telescope is equipped with a dual-speed 2-inch focuser, which provides precise control over focusing. This dual-speed design allows users to achieve sharp focus when observing high-magnification targets, making it easier to lock onto and appreciate fine details in distant objects. The EON 72MM also includes a 1.25-inch adapter, providing versatility in the selection of eyepieces.

Another prominent aspect of the Orion EON 72MM is its lightweight construction. Weighing in at just under 5 pounds, the telescope is highly portable, allowing astronomers to easily transport it to remote viewing locations or set it up in their backyard for a quick stargazing session. The telescope also includes a sturdy, adjustable mount that provides stability during use and enhances the overall viewing experience.

In addition to its optical quality and physical characteristics, the EON 72MM boasts impressive build quality with a robust aluminum body. The telescope’s finish is designed to withstand the rigors of transport and frequent use while offering aesthetic appeal. Moreover, with a retractable dew shield, the EON 72MM reduces the chances of dew forming on the lens, ensuring clearer views even during long observing sessions.

Overall, the Orion #9781 EON 72MM is an exemplary telescope that combines portability, excellent optics, and user-friendly features. Whether you're a beginner eager to embark on your astronomical journey or an experienced observer seeking a compact option for rich celestial views, the EON 72MM delivers superb performance and reliability, making it a valuable addition to any astronomer's toolkit.