Carson Optical RP-200 Calculating Power, Understanding Celestial Movement, Using the Telescope

Calculating Power:

The magnification of a telescope depends on both the focal length of your telescope as well as the eyepiece you use. There is a simple formula you can use to determine the magnification you are using at any given time. Simply divide the focal length of the telescope by the focal length of the eyepiece. For example, if you are using the 20mm eyepiece with your TP-200 telescope the power would be:

Power = 500mm / 20mm = 25x

Using an eyepiece with a smaller focal length will increase the magnification of your telescope. It is always best to start at the lowest magnification con- figuration. The wider field of view makes it easier to spot far away objects. Once an object is centered in your field of view you can switch to the higher power configurations.

Understanding Celestial Movement:

In order to get the most enjoyment out of your telescope it is necessary to know the basics of how celestial objects move across the sky. Due to the ro- tation of the earth, celestial objects appear to move from East to West across the sky, much like the Sun. You will notice this movement as an object in your telescope field of view will slowly move across the field and out of view. Continuous adjustment is needed to keep an object in the field of view.

Using the Telescope:

Once you have properly assembled and aligned your telescope you are finally ready to start using it.

• To locate an object using the telescope, first loosen the altitude lock (Fig. 3-20) allowing the telescope to rotate along both axes. Look through the finder scope (Fig. 1-4) to sight the object you are look- ing for and center it in the finder scope cross-hairs. You may need to focus the finder scope by turning the finder scope focus knob (Fig.

4-22). Then re-tighten the altitude lock.

• It is best to use the lowest power eyepiece (the Kellner 20mm eye- piece) at first. This allows for a wider field of view making it easier to locate objects. Once the object is centered in the field of view you can switch the eyepiece to higher magnifications.

•Once the object is centered in the field of view, turn the focus knobs (Fig. 1-6) until the image is clear and sharp. If the focus knobs are locked, loosen the focuser draw tube lock (Fig. 5-23) before turning the knobs.

•You will notice that the object you are viewing will slowly move across the field of view (caused by the rotation of the Earth). You will need to turn the slow motion cables (Fig. 1-8,9) to keep the ob- ject centered.

•The orientation of the image you see through both the finder scope and eyepiece of this telescope is normal. This allows you to use this telescope effectively when viewing terrestrial as well as astronomical objects.

There are many conditions that may affect your ability to focus or observe celestial objects clearly.

• Brightly lit areas (light pollution) will make it difficult to see faint objects in the sky. It will also make it difficult for your eyes to adjust to the dark. You should try and find a dark area and allow your eyes to adjust to the dark before making observations. Using a red filtered flashlight to view charts and your telescope components is recom- mended to preserve your night sight. The best viewing conditions are when the sky is inky black.

• Hazy skies, pollution, clouds and moisture can all affect the clarity of your viewing image.

• Avoid touching the eyepiece or optical tube while looking through the telescope. The vibrations caused by this contact will cause the object you are looking at to move. You should also make sure that the surface you place your telescope on does not vibrate or move as this will also cause your viewing object to move.

• You should avoid setting up your telescope inside a room looking through an open window. The difference in air temperatures may result in a blurry image.

• Viewing through a closed window might also result in a distorted im- age due to the varying densities of window glass.

• Avoid viewing objects that are low on the horizon. Objects that are higher up in the sky will appear much sharper.

• Sudden changes in temperature may cause condensation to appear on the optical components of the telescope. It is best to set up your telescope ahead of time and then wait while the telescope adjusts to the new temperature before using it.

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