1200 mm = 120x
10 mm
The maximum attainable magnification for a telescope is directly related to how much light its optics can collect. A tele- scope with more
More typically, useful magnifications will be limited to 200x or less, regardless of aperture. This is because the Earth’s “see- ing,” the atmosphere will be still and will yield the least amount of distortion. On nights of poor seeing, the atmosphere will be turbulent, which means different densities of air are rapidly mixing. This causes significant distortion of the incoming light, which prevents sharp views at high magnifications.
Keep in mind that as magnification is increased, the bright- ness of the object being viewed will decrease; this is an inherent principle of the physics of optics and cannot be avoided. If magnification is doubled, an image appears four times dimmer. If magnification is tripled, image brightness is reduced by a factor of nine!
Use of 2-Inch Eyepieces (XT8 and XT10 only)
All SkyQuest telescopes are designed to accept eyepieces with a barrel diameter of 1.25". The XT8 and XT10 have 2" focusers that accept both 1.25" and optional 2" eyepieces. At low magnifications, 2" eyepieces can provide a wider field of view than standard 1.25" eyepieces. A wider field can be desirable for viewing extended
To use 2" eyepieces, simply loosen the two large thumbscrews on the 2" adapter that are just in front of the thumbscrew that holds the provided 1.25" adapter in place. Once these thumb- screws are loosened the adapter comes off, exposing the 2" diameter focuser drawtube Now, insert your 2" eyepiece into the drawtube and secure with the two thumbscrews loosened previously, and you’re ready to observe.
Tube Balance
SkyQuest IntelliScope Dobsonians are designed to balance with standard supplied accessories, such as an eyepiece and a finder scope. But what if you want to use a larger finder scope or a heavier eyepiece? Traditional Dobsonian designs require the user to compensate by adding weight to the oppo- site end of the telescope tube. Such counterweighting systems can be expensive and unwieldy. The CorrecTension system of the SkyQuest IntelliScope Dobsonians, however, solves the finicky balance problem. The brake pads press against the alti- tude bearings on the optical tube and increase the friction. With CorrecTension, the added weight of
Carrying the Telescope
Transporting the SkyQuest is easy to do. The tube uncouples from the base and each component can be carried separate- ly. The base has a handle for easy carrying. With the retaining and tensioning knobs of the CorrecTension(XT) system hold- ing the optical tube captive on the base, the entire telescope can be carried as one unit. (This is not practical for the XT10 due to its hefty weight and size.) This requires some caution, however. If the telescope is lifted improperly, the tube could swing down and hit the ground.
First, point the optical tube straight up (vertical). Remove any eyepieces from the telescope and eyepiece rack, and place them in an eyepiece case. Grasp the handle on the front of the base with one hand while supporting the telescope tube vertically with the other (Figure 17). Now, lift the telescope by the handle. Once the telescope is in the horizontal position, you can carry the entire unit with one hand while supporting the optical tube with the other hand.
If you wish to carry the optical tube and base separately, sim- ply unthread the retaining and tensioning knobs until they are free of the base and optical tube (make certain spacer does not fall off the retaining knob). Lift the tube off the base then
Figure 17. Picking up and carrying the SkyQuest IntelliScope as a single unit (with tube held captive on the base) requires some caution. (a) First, position the tube vertically. Then grasp the handle on the base with one hand while supporting the tube with the other. This ensures that the tube will not swing down and impact the ground (b) With knees bent, slowly lift the base while supporting the tube. (c) As you lift, continue to support the tube with one hand to keep it parallel with the ground. Make sure you are comfortable with the weight of
a.the whole assembly before attempting the carry it!
b.c.
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