5
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)
= Magnification
Eyepiece Focal Length (mm)
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-
Figure 4.3.
Orientation of the mounting block when reversed to
balance the telescope for heavier accessories.
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.
