Orion 70MM AZ instruction manual Do You Wear Eyeglasses?, Focusing the Telescope

Altitude

Azimuth

Figure 5. The Observer 70 has two axes of motion: altitude

Do You Wear Eyeglasses?

If you wear eyeglasses, you may be able to keep them on while you observe. In order to do this, your eyepiece must have enough “eye relief” to allow you to see the entire field of view with glasses on. You can try looking through the eyepiece first with your glasses on and then with them off, to see if the glasses restrict the view to only a portion of the full field. If the glasses do restrict the field of view, you may be able to observe with your glasses off by just refocusing the telescope to your unaided vision.

If your eyes are astigmatic, images will probably appear best with glasses on. This is because a telescope’s focus- er can accommodate for nearsightedness or farsighted- ness, but not astigmatism. If you have to wear your glasses while observing and cannot see the entire field of view, you may want to purchase additional eyepieces that have longer eye relief.

and azimuth.

To move the telescope in the azimuth direction, loosen the azimuth lock knob, take hold of the telescope and gently rotate it to the desired position. Then re-tighten the azimuth lock knob. To move the telescope in the altitude direction, loosen the altitude lock knob, take hold of the end of the optical tube and move the tube up or down to the desired position. Then re-tighten the altitude lock knob.

Note about the Altitude Micro-Motion Rod and Thumb­ wheel: Since making fine adjustments to the altitude of the telescope can be tricky, the Observer 70 comes with an alti- tude micro-motion rod and thumbwheel (13). By turning the thumbwheel, the telescope will move very slightly either up or down, depending on which direction you turn the thumbwheel. Since there is a limit to how far the thumbwheel can turn in

Long eye relief allows full field of view to be seen with or without eyeglasses.

Short eye relief restricts the field of view for eyeglass wearers.

either direction, if you need to make any large altitude move- ments to the telescope, it is best to simply loosen the altitude lock knob (19) and move the scope by hand.

Focusing the Telescope

With the 25mm Explorer II eyepiece (3) inserted into the 90° mirror star diagonal (2) and secured with the thumbscrews, aim the optical tube (1) so the front (open) end is pointing in the general direction of an object at least 1/4-mile away. Look in the eyepiece and, with your fingers, slowly rotate one of the focus wheels (15) until the object comes into sharp focus. Go a little bit beyond sharp focus until the image starts to blur again, then reverse the rotation of the knob, just to make sure you’ve hit the exact focus point.

Operating the EZ Finder II reflex finder

The EZ Finder II reflex finder (4) (Figure 6) works by project- ing a tiny red dot onto a lens mounted in the front of the unit. When you look through the EZ Finder II, the red dot will appear to float in space, helping you locate even the faintest of deep space objects. The red dot is produced by a light-

emitting diode (LED), not a laser beam, near the rear of the sight. A replaceable 3-volt lithium battery provides the power for the diode.

To use the EZ Finder II, turn the power knob clockwise until you hear a “click” indicating that power has been turned on. With your eye positioned a comfortable distance from the back of the sight, look through the back of the reflex sight with both eyes open to see the red dot. The intensity of the dot can be adjusted by turning the power knob. For best results when stargazing, use the dimmest possible setting that allows you to see the dot without difficulty. Typically, a dim setting is used under dark skies and a bright setting is used under light-pol- luted skies or in daylight.

At the end of your observing session, be sure to turn the power knob counterclockwise until it clicks off. When the two white dots on the EZ Finder II’s rail and power knob are lined up, the EZ Finder II is turned off.

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