Orion ED EQ Alignment of the Polar Axis Finder Scope, Using the Polar Axis Finder Scope

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Alignment of the Polar Axis Finder Scope

1.Look through the polar finder at a distant object (during the day) and center it in the crosshairs. You may need to adjust the latitude adjustment L-bolts and the tripod posi- tion to do this.

2.Rotate the mount 180° about the R.A. axis. Again, it may be convenient to remove the counterweights and optical tube first.

3.Look through the polar finder again. Is the object being viewed still centered on the crosshairs? If it is, then no further adjustment is necessary. If not, then look through the polar finder while rotating the mount about the R.A. axis. You will notice that the object you have previously centered moves in a circular path. Use the three align- ment setscrews on the polar axis finder to redirect the crosshairs of the polar finder to the apparent center of this circular path.

4.Repeat this procedure until the position that the cross- hairs point to does not rotate off-center when the mount is rotated in R.A. Once this is accomplished, retighten the thumbscrews.

The polar axis finder scope is now ready to be used. When not in use, replace the plastic protective cover to prevent the polar finder from getting bumped, which could knock it out of alignment.

Using the Polar Axis Finder Scope

The reticle of the polar axis finder scope for the SkyView Pro has a tiny star map printed on it that makes precise polar alignment quick and easy. If you do not have a clear view of Polaris from your observing site, you will not be able to use the polar axis finder to precisely polar align the telescope. To align the mount using the polar axis finder scope, follow these instructions:

Figure 12. The optical tube must be at a 90° angle to the right ascension axis in order to view through the polar axis finder.

1.Approximately polar align the mount as outlined in the pro- cedure above.

2.Loosen the Dec. lock lever and rotate the optical tube on the declination axis so that the tube is at a 90° to the right ascension axis (Figure 12). This is so you can view through the mount with the polar axis finder. Tighten the Dec. lock lever.

3.Remove the cap on the front of the equatorial mount (Figure 8), and focus the polar finder by rotating the eyepiece.

4.Now, sight Polaris in the polar axis finder scope. If you have followed the approximate polar alignment procedure accurately, Polaris will probably be within the field of view. If not, move the tripod left-to-right, and adjust the latitude up-and down until Polaris is somewhere within the field of view of the polar axis finder scope.

5.Shine a red flashlight down the front end of the polar finder to illuminate the reticle within the field of view. Make sure the flashlight shines in at an angle, so as not to block the polar finder’s field of view. It may be helpful to have a friend hold the flashlight while you look through the polar finder. Note the constellation Cassiopeia and the Big Dipper in the reticle. They do not appear in scale, but they indicate the general positions of Cassiopeia and the Big Dipper relative to the north celestial pole (which is indicated by the cross at the center of the reticle). Rotate the reticle so the constellations depicted match their current orientation in they sky when viewed with the naked eye. To do this, release the R.A. lock lever and rotate the main telescope around the R.A. axis until the reticle is oriented with sky. For larger optical tubes, you may need to remove the tube from the mount to prevent it from bumping into the mount. Once the reticle is correctly oriented, use the right ascen- sion lock lever to secure the mount’s position.

6.Now use the azimuth adjustment knobs (Figure 10) and the latitude adjustment L-bolts (Figure 8) on the mount to position the star Polaris inside the tiny circle marked “Polaris” on the finder’s reticle. You must first loosen the knob underneath the equatorial mount on the center sup- port shaft to use the azimuth adjustment knobs. Once Polaris is properly positioned within the reticle, you are precisely polar aligned. Retighten the knob underneath the equatorial mount

From this point on in your observing session, you should not make any further adjustments in the azimuth or the latitude of the mount, nor should you move the tripod. Doing so will undo the polar alignment. The telescope should be moved only about its right ascension and declination axes.

Additional Note Regarding Focusing the Polar Axis Finder Scope

The polar axis finder scope is normally focused by simply rotating the eyepiece focus ring. However, if after adjusting the focus ring you find that the image of the reticle is sharp, but the stars are out of focus, then you must adjust the focus of the polar axis finder’s objective lens. To do this, first remove

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Contents Orion Finder scope Assembly Table of ContentsParts List UnpackingInstalling the Finder Scope Balancing the Telescope Inserting the Diagonal and EyepieceFocusing the Telescope Using Your TelescopeViewing with Eyeglasses Magnification & Eyepieces Focusing the Finder ScopeAligning the Finder Scope 900 mm = 25 mmUse of 1.25 Eyepieces without a Diagonal Setting Up and Using the Equatorial MountPolar Alignment Polar Alignment Using an Optional Polar Axis Finder Scope Optional polar axis finder scopeUsing the Polar Axis Finder Scope Alignment of the Polar Axis Finder ScopeTracking Celestial Objects Understanding the Setting CirclesCalibrating the Declination Setting Circle Optional Motor Drives for Automatic TrackingAstronomical Observing Calibrating the Right Ascension Setting CircleFinding Objects With the Setting Circles Confused About Pointing the Telescope?Let Your Eyes Dark-Adapt Seeing and TransparencyCooling the Telescope Eyepiece SelectionSun Astronomical ObjectsMoon PlanetsHow to Find Deep-sky Objects Starhopping Terrestrial ObservingPlanetary Photography AstrophotographyMoon Photography Piggyback PhotographySpecifications Care and MaintenanceCleaning Lenses One-Year Limited Warranty