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  How Do I Polar Align the Telescope?  
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Skip the Intro and Mount Setup Steps
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Going Polar
Good polar alignment is a vital step in getting the telescope tracking well enough to take great astronomy images. When Polar aligned the telescope's mount will be aligned with the polar axis of the Earth. Therefore, the telescope will only need to use its RA (left/right) drive system to track the objects of the night sky. Getting everything set up and aligned properly can seem like quite a chore at first but its only slightly more complicated than setting up in Alt/Az. (Okay, a bit more complicated than "slightly.").

This section will take you through the physical setup procedure, scope orientation, and software settings to lead you to a successful polar alignment.

This section assumes the use of the Meade standard field tripod and the Meade Superwedge although most of the instructions can be applied to other tripods and wedges.

Attaching the Tripod and Superwedge
Make sure you have securely attached the "tangent arm" to the head of the tripod with both of the supplied bolts. Place the Superwedge on the tripod and make sure the steel pin on the bottom of the Superwedge is inserted into the slot of the tangent arm. Secure the Superwedge to the head of the tripod with the 3 bolts and the central knob (with the compass) that are supplied with the Superwedge.

Tripod and Superwedge Orientation
Orient the tripod and Superwedge such that the tangent arm is pointing south. Using the Azimuth knobs located on the left and right hand sides of the Superwedge adjust the wedge in azimuth so that it is halfway between it's eastern-most and western-most points of travel. This is done to ensure you will have the full range of motion available to you when you attempt to align the OTA with Polaris.

Using just your eye, line up the top notch of the latitude plate with Polaris as best as you can. This is done simply to achieve a rough polar alignment so that you won't have to move the entire telescope, tripod, and Superwedge after everything is mounted and in place. Adjust the height of the tripod to your liking and level the tripod and wedge. It is best to use a relatively long bubble level in at least 2 axes rather than the built-in bubble level.

Note:
If you're doing this during the day, just use the built-in compass to line it up with north and make sure to factor in your local magentic declination from true north based on your location - most of southern California has a magnetic declination of about 14 degrees.

Telescope, Superwedge, and Tripod - Together at Last
Now that the tripod and wedge are attached to each other, roughly aligned, and leveled, it's time to put the telescope on the wedge, adjust some Autostar II settings, and align the OTA with the North Celestial Pole.

The bottom of the telescope base has 3 holes that are used to attach the telescope to the tilt plate of the wedge. Place a bolt in the hole that is directly opposite the control panel. Screw it into place about 4 or 5 turns so that it is well-threaded but so there is enough room for the tilt plate to go between the telescope base and the head of the bolt (about 1" of space). This one bolt will be used to anchor the telescope to the tilt plate of the Superwedge using the top notch on the tilt plate.

Lift the telescope and slide the bolt that's in the base of the telescope into the notch on the tilt plate of the wedge. Once you're sure the bolt is fully seated in the slot gently release the telescope. Continue screwing the bolt into place so that it is snug but not tight. Look through the 2 remaining holes in the tilt plate to align them with the 2 remaining holes in the base of the telescope. Insert the other 2 bolts and tighten all three.

You should now have your telescope mounted to the tilt plate of the Superwedge and be ready to refine your polar alignment. Double check the level of the wedge just to make sure nothing has moved too much.

Powering Up and Autostar Settings
If the Autostar is currently set to an Alt/Az mount perform the following:
  1. Power up the telescope.
  2. Cancel out of the GPS acquisition by pressing any key (this step is not necessary if GPS Alignment is set to occur on demand rather than at startup [applies to version 1.5c and later]).
  3. Go to SETUP > TELESCOPE > MOUNT and change the setting to Polar.
  4. Power down the telescope.
You may now restore power to the telescope. (Versions 1.4g and earlier will initialize the Smart Drive and attempt GPS signal acquisition; Versions 1.5c and later will not attempt GPS signal acquisition at this point and will only initialize the Smart Drive if PEC it turned on.)

Choose the "1 Star" POLAR alignment method. This method requires you to put the telescope in the POLAR Home position, center polaris when instructed, and align on one preselected star. It is a simple process and is quite accurate. Read on for details.

Polar Home Position
Getting the telescope in the Polar HOME position is a matter of placing the OTA at 00:00 HA (Hour Angle) and at 90 degrees in Declination (this will result in the finder scope being "upside down" and the telescope pointing toward Polaris or Sigma Octans in the Southern Hemisphere). This will get the telescope in, what I'll call, the "rough" Polar HOME position.


the "rough" polar home position
To refine the Polar HOME position and ensure better polar alignment you must make sure that the OTA is truly parallel to the fork arms. The indicators on the left fork arm simply don't provide the level of accuracy needed to make this adjustment. To refine the adjustment of the Polar HOME position you must perform the following:
  1. Place the telescope in the "rough" Polar HOME position, as just described. See photo above.
  2. Place a widefield eyepiece in the telescope's star diagonal and look through it.
  3. Adjust the slew speed to MAX. Look through the eyepiece and rotate the telescope back and forth in RA by pressing the East and West slew buttons.
    • Notice how the stars move. You want to orient the telescope so that the stars rotate around the center of the field of view.
    • Adjust the Declination position with the slow motion knob on the telescope (or with the hand controller) until the stars rotate around the center of the FOV. Use the wedge's latitude plate adjustment to recenter the stars each time you move the telescope in DEC.
    • If a star is in the center of the field of view it should pretty much remain in place as you move the telescope back and forth in RA.
Once you have positioned the OTA so that it is truly parallel with the fork arms, you may press ENTER.

Final Alignment
The ASII now assumes that the telescope is oriented exactly as it needs to be with the OTA parallel to the fork arms and pointing roughly toward Polaris. The telescope will now slew by an amount equal to the distance and direction Polaris is from the true North Celestial Pole for the current date and time. You must now use only the manual adjusters on the Superwedge to center Polaris in the eyepiece. Do not use the hand controller. It is best to use an illuminated reticle eyepiece for this procedure to ensure that the star is truly centered in the field of view.

Press ENTER once you have centered Polaris in the eyepiece.

The telescope will now slew to a second star that it automatically chooses. If this is an acceptable star, center it in the field of view (again using the illuminated reticle eyepiece), and press ENTER. If the star is not visible from your location, press the UP or DOWN arrow key on the hand controller (at the bottom of the controller) to select the next alignment star in the ASII database. Then center the star and press ENTER.

At this point you have acheived a basic polar alignment!



 Summary of Steps - Transitioning from Alt/Az
  1. Place a wedge on the tripod.
  2. Position the tripod and wedge so that the forks of the telescope will be pointing north once it is place on the wedge.
  3. If it's not in place already, set the telescope on the wedge and tripod.
  4. Power up the telescope.
  5. Tell the Autostar that the mount is POLAR.
  6. Choose the "1 Star" polar alignment method.
  7. Put the telescope in the POLAR Home position as instructed (start with the "rough" polar home position only but eventually you should learn how to refine the polar home position). Press ENTER.
  8. Center Polaris as instructed. Press Enter.
  9. Center the alignment star. Press Enter.


Summary of Steps - Starting Up a Polar Mounted Scope
  1. Power up the telescope.
  2. Choose the "1 Star" polar alignment method.
  3. Put the telescope in the POLAR Home position as instructed (start with the "rough" polar home position only but eventually you should learn how to refine the polar home position). Press ENTER.
  4. Center Polaris as instructed. Press Enter.
  5. Center the alignment star. Press Enter.


Summary of Steps - Quick Setup for Polar Aligned Scopes
  1. Power up the telescope.
  2. Find a bright star in the south near the Meridian and Celestial Equator. The star you choose must be in the ASII Named Stars database.
  3. Manually slew to the star you've chosen. Center the star in the eyepiece.
  4. Find this star in the ASII database (go to Star > Named > select your star). Press ENTER.
  5. SYNC on this star (hold down the ENTER button for about 3 seconds, release the button, then press ENTER when prompted).
  6. The telescope will now begin tracking the star. You should drift align for better alignment especially if you will be imaging.
See the following articles for related information:
Drift Alignment from DarkSkyImages.com
Superwedge Modifications
Improved Declination Indicator
What is the Polar HOME Position?



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