Orion ED102T CF #9530 Connecting the ED102T CF to a Telescope Mount, Using Different Eyepieces

Figure 4.1. The stock orientation of the ED80T CF mounting block.

Figure 4.2. Using the included 5mm hex key, remove the 2 socket head screws to reverse the orientation of the mounting block to balance the telescope for heavier accessories.

Figure 4.3. Orientation of the mounting block when reversed to balance the telescope for heavier accessories.

found on your camera tripod to the underside of the mounting block.

The mounting block also functions as a dovetail plate which is compatible with many Orion telescope mounts. The dovetail plate is also compatible with many other mounts. To connect the ED80T CF to a telescope mount, loosen the attachment screw(s) on the mount’s dovetail holder until the screw(s) pro- vides enough clearance for the dovetail mounting plate. Align the mounting block with the dovetail holder and slide it for-

ward. Tighten the attachment screw(s) on the dovetail holder of the mount.

If you are using a camera tripod or telescope mount and need additional balance adjustment, the orientation of the mounting block can be reversed. This is especially helpful when using heavy accessories, such as 2" eyepieces or DSLR cameras. To reverse the orientation of the mounting block, remove the two socket head screws (using the included 5mm hex key) that attaches the mounting block to the telescope tube and turn the block around 180° (Figure 4.1-4.3). Once the mount- ing block orientation has been reversed, reattach the two socket head screws.

Connecting the ED102T CF to a Telescope Mount

The ED102T CF refractor includes a preinstalled pair of tube rings and a dovetail mounting plate, ready to attach to a heavy-duty telescope mount. The dovetail plate is compatible with many Orion telescope mounts. The dovetail plate is also compatible with many other available mounts. To connect the ED102T CF to a mount, loosen the attachment screw(s) on the mount’s dovetail holder until the screw(s) provide enough clearance for the dovetail mounting plate. Carefully place the dovetail plate flat against the top surface of the dovetail holder of the mount and tighten the attachment screw(s) securely.

Balancing the ED102T CF can be achieved by sliding the dovetail mounting plate forward or backward within the mount’s dovetail holder. You can also move the telescope for- ward or backward within the tube rings. The tube rings offer the most adjustment range. Loosen the tube ring clamps slightly and slide the telescope tube forward or backward as needed to reach optimum balance, then retighten the tube ring clamps.

Using Different Eyepieces

The ED T CF refractors work well with virtually any 1.25" or 2" eyepiece. Because the ED T CF refractors implement high- quality ED optics, the eyepieces you use should also have excellent, fully multi-coated optics to utilize the full perfor- mance of the telescope.

It is desirable to have a range of eyepieces of different focal lengths, to allow viewing over a range of magnifications. To calculate the magnification, or power, of a telescope, simply divide the focal length of the telescope by the focal length of the eyepiece:

Telescope Focal Length (mm)

Eyepiece Focal Length (mm) = Magnification

If all outside viewing conditions are ideal, every telescope with good optics supports a maximum of about 60x per inch, or 2.4x per millimeter, of aperture. Keep in mind that at higher powers, an image will always be dimmer and less sharp (this is a fundamental law of optics). In most cases the steadiness of the air (the “seeing”) will limit how much magnification the scope can tolerate, rather than the telescope itself.

Always start viewing with your lowest-power (longest focal length) eyepiece in the telescope. After you have located and observed the object with it, you can try switching to a higher-

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