Focusing, Calculating Magnification | Celestron 21035 specs

Focusing

To focus your Travel Scope turn the focus knob located near the rear of the telescope (see Figure 1-1). Turning the knob counterclockwise allows you to focus on an object that is farther than the one you are currently observing. Turning the knob clockwise from you allows you to focus on an object closer than the one you are currently observing.

Note: Remove the front lens cap of the Travel Scope optical tube prior to attempting your observation.

Note: If you wear corrective lenses (specifically glasses), you may want to remove them when observing with an eyepiece attached to the telescope. If you have astigmatism, corrective lenses should be worn at all times.

Calculating Magnification

You can change the power of your telescope just by changing the eyepiece (ocular). To determine the magnification of your telescope, simply divide the focal length of the telescope by the focal length of the eyepiece used. In equation format, the formula looks like this:

Focal Length of Telescope (mm)

Magnification = ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯

Focal Length of Eyepiece (mm)

Let’s say, for example, you are using the 20mm eyepiece that came with your telescope. To determine the magnification you divide the focal length of your telescope (the Travel Scope for this example has a focal length of 400mm) by the focal length of the eyepiece, 20mm. Dividing 400 by 20 yields a magnification of 20x.

Although the power is variable, every telescope under average skies has a limit to the highest useful magnification. The general rule is that 60 power can be used for every inch of aperture. For example, the Travel Scope is 2.8” inches in diameter. Multiplying 2.8 by 60 gives a maximum useful magnification of 168 power. Although this is the maximum useful magnification, most of your observing will be done at low powers which generate brighter and sharper images.

Note on Using High Powers – Higher powers are used mainly for lunar and sometimes planetary observing where you can greatly enlarge the image, but remember that the contrast and brightness will be very low due to the high magnification.

You can purchase optional eyepieces to give you a range of powers you can observe with. Visit the Celestron website to see what is available.

21035 specifications

The Celestron 21035 is a high-quality, versatile telescope that caters to both novice and experienced astronomers. This reflector telescope is part of the AstroMaster series, known for its ease of use, excellent optical performance, and sturdy construction. One of its standout features is the 70mm aperture, which allows for bright and clear images of celestial objects. The larger the aperture, the more light the telescope can gather, making it ideal for viewing the Moon, stars, and even some of the more distant planets in our solar system.

One of the key technologies integrated into the Celestron 21035 is its fully coated glass optics. The objective lens and the eyepieces feature multiple layers of coatings, enhancing light transmission and delivering sharper images with improved contrast. This optical design ensures that both the colors and details of celestial objects are rendered accurately, which is crucial for astronomical observation.

Ease of setup is another highlight of the Celestron 21035. The telescope comes with a pre-assembled mount and optical tube, allowing users to get started with minimal effort. The simple, intuitive design is perfect for beginners who want to dive into stargazing without being overwhelmed by complicated setup processes. The lightweight and portable nature of the telescope makes it easy to transport, whether you are going to a local observatory or simply heading to your backyard for some nighttime exploration.

Additionally, the Celestron 21035 features an adjustable, full-height tripod that provides sturdy support, minimizing vibrations and maintaining stability while observing. The mount is manually operated with slow-motion controls, enabling precise targeting of celestial objects. Users can easily track their target as it moves across the sky, enhancing the viewing experience.

For those who enjoy astrophotography, the Celestron 21035 offers the option to attach a smartphone or a camera, allowing you to capture stunning images of the night sky. The telescope's versatility is further highlighted by its compatible eyepiece sizes, providing users with the ability to swap in different magnifications based on their interests.

In summary, the Celestron 21035 is an excellent choice for anyone looking to explore the wonders of the universe. With its robust optical performance, user-friendly design, and impressive features, it serves as a reliable tool for amateur astronomers and seasoned stargazers alike. Whether you’re observing lunar craters or distant galaxies, the Celestron 21035 promises an enjoyable and enriching experience under the stars.