APPENDIX A: Calculating Eyepiece Power

The power, or magnification of the telescope depends on two optical characteristics: the focal length of the main telescope and the focal length of the eyepiece used dur- ing a particular observation. The focal length of the 4504 telescope is fixed at 910mm. To calculate the power in use with a particular eyepiece, divide the focal length of the eyepiece into the focal length of the main telescope. E.g., using the H 25mm eyepiece supplied with the telescope, the power is calculated as follows:

Power =

telescope focal length

= 910mm

= 36x

 

eyepiece focal length

25mm

 

The maximum practical magnification is determined by the nature of the object being observed and, most importantly, by the prevailing atmospheric conditions. Generally powers of perhaps 35x to 175x will be useful most often, consistent with high image resolution. When unsteady air conditions prevail (as witnessed by rapid “twinkling” of the stars), extreme high-power results in “empty magnification,” where the object detail observed is actually diminished by the excessive power.

The 3x Barlow lens included with your telescope triples the eyepiece magnification. To calculate the power of an eyepiece used with a Barlow lens, multiply the eyepiece power by the Barlow value. E.g., using the H 25mm eyepiece, the power or magnifi- cation of the 4504 telescope (as calculated in the example above) is 36x and the Barlow value is 3x. The total power using the Barlow lens is:

Total power = eyepiece power x Barlow value = 36 x 3 = 108x

To install the Barlow lens, first place the Barlow lens into the focuser assembly (remove the focuser dustcap, if necessary), followed by the eyepiece (Fig. 30). Tighten the Barlow thumbscrews and the focuser thumbscrews to a firm feel only.

Eyepiece

Thumbscrew

Barlow

Focuser

Thumbscrew

Assembly

 

 

Focus knob

Fig. 30: Insert Barlow into focuser assembly.

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Meade 4504 instruction manual Appendix a Calculating Eyepiece Power, Insert Barlow into focuser assembly
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4504 specifications

The Meade 4504 is a notable member of Meade Instruments’ extensive line of telescopes, designed for both beginners and experienced astronomers. This telescope is known for its user-friendly features and impressive optical performance, making it an excellent choice for stargazers keen on exploring the night sky.

One of the key features of the Meade 4504 is its 4.5-inch aperture, a critical factor that determines the amount of light the telescope can gather. This larger aperture allows users to observe fainter celestial objects, from nebulae to distant galaxies, with clarity and detail. The telescope is equipped with a Newtonian reflector design, which utilizes a primary mirror to collect light and a secondary mirror to direct it to the eyepiece. This design effectively eliminates chromatic aberration, offering sharp and crisp images.

The Meade 4504 also boasts a mount that is robust yet user-friendly. It typically comes with an Altazimuth mount, which allows for smooth movement both vertically and horizontally. This makes it easier to track celestial objects as they move across the sky. The mount's stability is crucial during high-magnification viewing, as it minimizes vibrations and provides a steady image.

A standout feature of the Meade 4504 is its ease of assembly and operation. Designed with beginners in mind, it usually includes a straightforward setup guide that allows users to get their telescope ready for use quickly. Additionally, the telescope often comes with a finderscope, which helps in locating objects in the night sky, a crucial tool for novice astronomers still learning to navigate the cosmos.

In terms of accessories, the Meade 4504 often includes a variety of eyepieces, allowing users to switch magnifications for different viewing experiences. These eyepieces enhance the versatility of the telescope, catering to varied interests, whether it's observing planets within our solar system or examining the details of various star clusters.

Overall, the Meade 4504 represents a balance of quality, convenience, and affordability, making it an ideal choice for anyone looking to embark on a journey of astronomical discovery. It effectively brings the universe closer to home, allowing enthusiasts to explore the wonders of space with ease. Whether you are a first-time observer or someone with a passion for celestial exploration, the Meade 4504 offers a remarkable gateway to the night sky.
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