Coleman AT70 - How to Use Your Coleman AT70; Finder Scope Alignment; Daylight Settings; About Magnification

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HOW TO USE YOUR COLEMAN AT70
A.
FINDER SCOPE ALIGNMENT
Since a telescope by design has a narrow field of view, it can be challenging to locate the
particular object you wish to view. For this reason the telescope is fitted with a low-power,
wide-field miniature optical device called a finderscope. Always use your finderscope to first
locate the object you would like to view. The finderscope should be aligned with the main
telescope tube before you begin using the telescope, in order that both the telescope and
finder scope are positioned to provide exactly the same angle and view.
Note: Objects in the finder scope are upside down. This is normal and is common to
all astronomical telescopes.
B. COMPLETE THE FOLLOWING SETTINGS IN DAYLIGHT:
1) With either the K10 or K25 eyepiece in the erecting diagonal prism, rotate the tripod head
toward an object you have selected to view. Direct the tripod head to an easily recognizable,
stationary object that is at least 200-300 feet away.
2) When the telescope is pointing in the general direction of the object you wish to view,
adjust the horizontal position and vertical elevation (up and down angle). The vertical
elevation adjustment is done by rotating the elevation adjustment knob (10), or by gently
moving the telescope up or down until it is aligned with the object to be viewed. You may lock
the telescope into position with the elevation locking knob (11).
3) Look through the finderscope (6) and refine the elevation as described above. Center the
object in the field of view. You may also adjust the finderscope by simply releasing one of the
small adjusting screws holding the finderscope and re-position the finder scope until the
object is centered within the X-shaped crosshairs.
4) All screws should be completely tightened as soon as the view through the finder scope
coincides with the view of the main telescope.
5) You may need to repeat this procedure to ensure a perfect alignment.
6) Look through the eyepiece and focus the image by slowly rotating the pinion focusing
knobs. These knobs are located at the rear of the telescope optical tube.
7) For the various telescope powers, please refer to the next section ABOUT
MAGNIFICATION.
C. ABOUT MAGNIFICATION:
The magnification power of a telescope indicates how much an image is enlarged or how big
and close it appears to the viewer. The focal length of the eyepiece, combined with the focal
length of the telescope, determines the magnification power. To calculate the power of your
telescope with any particular eyepiece, simply divide the focal length of the telescope (400mm)
by the focal length of the eyepiece (indicated in “mm” on the eyepiece collar).