A telescope is an instrument that collects and focuses light. The nature of the optical design determines how the light is focused. Some telescopes, known as refractors, use lenses. Other telescopes, known as reflectors, use mirrors. The Maksutov-Cassegrain optical system uses a combination of mirrors and lenses and is referred to as a compound or catadioptric telescope. This unique design offers large-diameter optics while maintaining very short tube lengths, making them extremely portable. The Maksutov- Cassegrain system consists of a corrector plate, a spherical primary mirror, and a secondary mirror spot. Once light rays enter the optical system, they travel the length of the optical tube three times.

Figure 6-1

A cutaway view of the light path of the Maksutov-Cassegrain optical design

The optics of the NexStar have enhanced multi-layer coatings on the primary and secondary mirrors for increased reflectivity and a multi coated corrector for the finest anti-reflection characteristics.

Inside the optical tube, a black tube extends out from the center hole in the primary mirror. This is the primary baffle tube and it prevents stray light from passing through to the eyepiece or camera.

Image Orientation

The image orientation changes depending on how the eyepiece is inserted into the telescope. The NexStar uses three reflective surfaces to bounce the light to the eyepiece. This produces an image that is right-side-up, but reversed from left-to-right (i.e., reversed). This is normal for the Maksutov-Cassegrain design.

Fig 6-2a - Actual image

orientation as seen with the

unaided eye

Fig 6-2b - Reversed from left to

right, as viewed through the

eyepiece

24

Page 23 Page 25
Page 24
Image 24
Celestron NexStar HC manual Image Orientation
Page 23 Page 25

NexStar HC specifications

The Celestron NexStar Hand Controller (HC) is an advanced control unit designed to enhance the astronomical observation experience for both novice and experienced stargazers. This innovative device is an integral part of the NexStar telescope series and offers a range of features that simplify the process of locating celestial objects.

One of the main features of the NexStar HC is its user-friendly interface. The controller is equipped with a large, illuminated LCD screen that displays essential information clearly, even in low-light conditions. The layout is intuitive, allowing users to quickly familiarize themselves with its functions. The keypad includes dedicated buttons for common tasks, making it easy to navigate the expansive database of celestial objects.

The NexStar HC boasts an impressive database containing over 40,000 celestial objects, making it a powerful tool for astrophotography and observational astronomy. Users can access planets, stars, galaxies, and nebulae at the touch of a button. The built-in database allows for precise and efficient locating of objects, significantly reducing the time spent searching the night sky.

One of the standout technologies featured in the NexStar Hand Controller is the GoTo functionality. This advanced tracking technology enables the telescope to automatically locate and track celestial objects with high precision. By entering the desired object into the controller, users can allow the telescope to autonomously adjust its position, providing a hassle-free experience.

Additionally, the NexStar HC supports various alignment methods, including SkyAlign, AutoAlign, and One-Star Align. These alignment techniques assist in calibrating the telescope for optimal tracking and positioning. The SkyAlign method, in particular, allows users to point the telescope at any three bright stars, and the HC will calculate the telescope's location in relation to those stars, making alignment accessible even for beginners.

The NexStar Hand Controller is also compatible with Celestron’s StarSense technology, enabling automatic alignment using a smartphone. This feature allows users to refine their observations seamlessly and provides a modern twist to traditional stargazing methods.

Other notable characteristics include programmable go-to tracking speeds and the ability to save user-defined locations. The controller’s ergonomic design ensures comfort during long observing sessions, while the robust build quality guarantees durability.

In summary, the Celestron NexStar Hand Controller combines a wealth of features and cutting-edge technologies to enhance the stargazing experience. Its user-friendly interface, extensive database, versatile alignment methods, and compatibility with advanced tracking systems make it an indispensable tool for anyone looking to explore the wonders of the night sky.
Top Page Image Contents