Celestron NexStar HC manual The Hand Control, The Eyepiece, EyepieceStarPointer Diagonal

The Hand Control

The hand control is located on the side of the fork arm and can be removed and used remotely or used while attached to the fork. The hand control attaches to the fork arm by resting on two posts, located on the bottom of the hand control cradle, and a clip inside the fork arm. To remove the hand control from the fork arm cradle, gently lift the hand control upwards and pull out. To return the hand control into the fork arm, lower the hand control into the cradle so that the two holes in the bottom of the hand control go over the posts on the bottom of the cradle, and the opening in the back of the hand control slides over the clip inside the fork arm.

Once the telescope is powered up, the hand control can be used to move the optical tube in altitude (up and down) and azimuth (side to side).

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Press UNDO (for GT model only). This will bypass the normal alignment procedures and will still allow you to control the telescope.

Use the Up arrow directional button to move the telescope tube until it is roughly parallel to the ground. This will make it more convenient to attach the necessary accessories as well as remove the front lens cover and install batteries when they are needed.

You are now ready to attach the included visual accessories onto the telescope optical tube.

The Eyepiece

The eyepiece, or ocular, is the optical element that magnifies the image focused by the telescope. The NexStar 4 has an internal diagonal mirror that diverts light to the eyepiece barrel on top of the telescope's rear cell. The eyepiece fits into the barrel built-in to the rear cell. To install the eyepiece:

1.Loosen the thumbscrew on the eyepiece barrel so it does not obstruct the inner diameter of the barrel.

2.Slide the chrome portion of the eyepiece into the eyepiece barrel.

3.Tighten the thumbscrew to hold the eyepiece in place.

To remove the eyepiece, loosen the thumbscrew on the star diagonal and slide the eyepiece out.

Eyepieces are commonly referred to by focal length and barrel diameter. The focal length of each eyepiece is printed on the eyepiece barrel. The longer the focal length (i.e., the larger the number) the lower the eyepiece power or magnification; and the shorter the focal length (i.e., the smaller the number) the higher the magnification. Generally, you will use low-to-moderate power when viewing. For more information on how to determine power, see the section on “Calculating Magnification.”

EyepieceStarPointer

Diagonal

Barrel

Flip Mirror Control

Focuser Knob

Figure 3-2 – The Rear Cell with Visual Accessories

Barrel diameter is the diameter of the barrel that slides into the telescope's eyepiece barrel. The NexStar uses eyepieces with a standard 1-1/4" barrel diameter.

Note:

As mentioned, the NexStar has an internal flip mirror that can divert light either through the eyepiece barrel at the top of the rear cell or directly through the photographic opening at the back of the rear cell. Make sure that the flip mirror is in the "up" position for viewing with an eyepiece and in the "down" position for taking photographs (see Astronomy Basics section of the manual).

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