Attaching a CCD Camera

The Orion f/3.9 Newtonian Astrographs are equipped to accept CCD cameras with a 2" nosepiece, or a 2" coma cor- rector in place of the nosepiece, which slides directly into the telescope’s focuser like an eyepiece (Figure 5). The 2" nosepiece is secured with the two thumbscrew locks. If your CCD imager does not include a compatible 2" nosepiece, or if you wish to utilize the camera’s T-threads without a coma cor- rector, a zero-profile prime focus camera adapter is required (available from Orion). The zero-profile adapter has male T-threads that couple to the female T-threads of your camera.

Note that, depending on your CCD camera’s specifications, you may need to add T-thread spacer rings between the coma corrector and the CCD camera, to achieve the necessary crit- ical distance between the coma corrector’s rear lens element and the camera’s imaging sensor.

Attaching a DSLR Camera

To attach a DSLR camera, you will need the appropriate T-ring for the make and model of your camera. If you do not plan to use a coma corrector, then you will need a zero-profile prime focus camera adapter (available from Orion). Simply attach the T-ring to the camera body and thread the zero-pro- file camera adapter into the T-ring. Then insert the barrel of the camera adapter into the focuser’s 2" accessory collar and secure it with the two thumbscrew locks (Figure 6).

To use a coma corrector, thread it into the T-ring attached to your DSLR camera body, then insert the coma corrector housing into the focuser through the 2" accessory collar and tighten the two locking thumbscrews on the collar to secure the camera in place.

Removing the Piggyback Camera Adapter from the Tube Ring

If you want to install an optional mounting plate atop the tube rings for piggyback attachment of a guide scope, you’ll need to remove the piggyback camera adapter first. To do so, first remove the tube ring from the telescope. Then unthread the plastic ring from the threaded bolt. Peel back the felt lining on the inside surface of the tube ring where the bolt is located; peel it back just enough so that you can access the bolt head with a screwdriver. Using a Phillips screwdriver, remove the bolt from the ring. Now, replace the adhesive felt over the area where the bolt head was. Now the rings are ready to accom- modate a mounting plate for your piggyback guide scope assembly.

The Orion f/3.9 Newtonian Astrographs were designed with a couple of special enhancements to maximize the contrast of your astrophotographs and visual images. One is the inclusion of multiple baffle rings on the interior of the optical tube. The 8" model has 9 baffle rings and the 10" model has 13. These baffle rings block the transmission of off-axis light through the optical tube, which could reduce image contrast. The other contrast-enhancing feature is the extended length of the opti-

2" Nosepiece

Figure 5. The Orion Parsec 8300 CCD camera, with 2" zero- profile adapter (nosepiece), which is included with the camera.

DSLR camera

Zero-profile camera adapter (not

visible)

2" Accessory collar

T-ring

Figure 6. Attachment of a DSLR camera requires a T-ring for the particular camera model and a T-adapter, such as the Orion Zero-Profile Prime Focus Camera Adapter, which fits into the 2" accessory collar.

1.25" Eyepiece	2" Slip-on
1.25" Eyepiece	adapter, 36mm	2" Thread-on
holder	extension	2" Thread-on
holder	extension	adapter, 30mm
		adapter, 30mm
		extension

Figure 7. The 1.25" eyepiece holder and two 2" extension adapters included with the 8" and 10" f/3.9 Newtonian Astrographs.

#8296 10" F/3.9, #8297 8" F/3.9 specifications

The Orion #8297 8" F/3.9 and #8296 10" F/3.9 reflect the latest innovations in astronomical technology, designed to meet the needs of both amateur and professional astronomers. These telescopes are renowned for their impressive optics, portability, and user-friendly features, making them ideal for deep sky observation and astrophotography.

The Orion #8297 8" F/3.9 features an 8-inch aperture, which allows for a remarkable light-gathering capacity, making it suitable for observing faint celestial objects. With a fast focal ratio of F/3.9, this telescope enables astronomers to capture stunning images of galaxies, nebulae, and star clusters with minimal exposure times. The telescope’s well-constructed primary mirror is made from high-quality glass, ensuring sharp and detailed views of the night sky. Additionally, the dual-speed 2” Crayford-style focuser enhances focusing precision, allowing users to achieve fine adjustments with ease.

On the other hand, the Orion #8296 10" F/3.9 elevates the observational experience with a larger 10-inch aperture. This increased size further enhances light-gathering ability, resulting in even clearer images of distant objects. Like its 8-inch counterpart, the F/3.9 focal ratio makes this telescope particularly advantageous for astrophotography, enabling users to shoot spectacular deep-sky images efficiently. The telescope is constructed with a sturdy, fully adjustable mount that ensures stability while tracking celestial objects, even during high-magnification viewing.

Both models come equipped with adjustable finderscopes, which assist in locating objects in the vast night sky, and they include a set of high-quality eyepieces that provide a range of magnifications to suit different observation needs. Furthermore, the lightweight design of both telescopes allows for easy transport to various observing sites, making them versatile tools for astrophotography enthusiasts and casual observers alike.

In summary, the Orion #8297 8" F/3.9 and #8296 10" F/3.9 are excellent telescopes that combine advanced optics with user-centric design. Their strong performance, portability, and innovative features make them perfect choices for anyone looking to explore the wonders of the universe, from novices to seasoned astronomers.