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I'm new to astronomy and recently got myself a telescope with an equatorial mount. I've found lots of resources online showing how to align the telescope but they all operate on the assumption that you live in the Northern Hemisphere and align to True North or Polaris.

What is the procedure for those of us who live on the other half of Earth? Pointing my telescope north, I still suffer problems finding and tracking objects in the sky.

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  • $\begingroup$ When you point your scope north with your latitude dialed in to the base, does it line up directly with Polaris? $\endgroup$ – Michael Sep 16 '17 at 20:42
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I'm going to post answers for both hemispheres, because there are good points from both sets of directions I've found.


For the northern hemisphere:

The "declination drift method" is the most accurate way to accomplish this. The method is straightforward, but it does require some time and patience.

  1. First, aim the mount's polar axis roughly at Polaris. Now point the telescope at a star that's somewhat above the celestial equator and as close to south as you can judge by looking opposite Polaris. Put in a high-power eyepiece. If the eyepiece has cross hairs, center the star on them. Otherwise put the star on the north or south edge of the field and defocus it a little. Turn on the clock drive, and ignore any east-west drift.
  2. If the star drifts south in the eyepiece, the polar axis is pointing too far east.
  3. If the star drifts north, the polar axis is too far west.
  4. Shift the polar axis left or right accordingly, until there is no more drift.
  5. Now aim at a star that's near the celestial equator low in the eastern sky.
  6. If the star drifts south, the polar axis points too low.
  7. If the star drifts north, the polar axis points too high.
  8. Again, shift the polar axis accordingly.
  9. Now go back and repeat from the beginning, because each adjustment throws the previous one slightly off. When all visible drift is eliminated the telescope is very accurately aligned, and you can take long deep-sky exposures.

Via Sky & Telescope

For the southern hemisphere:

Part 1

  1. Direct your telescope to a bright star that's low-ish (about 20 degrees) on the Eastern Horizon, near the Celestial Equator (i.e. 0 degrees DEC). The Orion nebula would be good to look at in mean time (given the right time of the year - as it may be too high or not visible).
  2. At this point, the east/west rotation of your mount has little effect, leaving you to correct the angle of elevation of the mount.
  3. Now, if the star drifts NORTH, your polar axis is too low - change the axis to angle further up in the sky (i.e. the latitude knob on your eq mount)
  4. But if the star drifts SOUTH, your plar axis is too high - change the axis to angle further down toward land (i.e. the latitude knob on your eq mount).
  5. You can tell if the star is drifting north or south by allowing the star to drift for a little bit - now, move your telescope to "catch up with the star" using the DEC control. If you see it heading north, then it's drifting north and vice-versa!

Part 2

  1. Now, point the telescope to a bright star on the Meridian and on the celestial equator i.e. right above your head somewhere. This is so the elevation of the mount (as corrected in the steps above) will have minumal effect, allowing you to accurately correct the east/west rotation of the mount.
  2. Now, if the star drifts NORTH, your polar axis is too far EAST - so rotate your mount further West (i.e. rotate your mount clockwise while looking down at it).
  3. Now, if the star drifts SOUTH, your polar axis is too far WEST - so rotate your mount further East (i.e. rotate your mount anti-clockwise while looking down at it).

Part 3

  1. Repeat these two steps a few times to increase the accuracy of your plar alignment - repeating Part 2 will allow you to get Part 1 more accurate.

Via OZScopes


Edit to provide less-precise-but-more-prompt method

Polar alignment for southern hemisphere observers is very similar to techniques used for the northern hemisphere. The major difference is the lack of a bright pole star like Polaris near the south celestial pole (SCP) to aid orientation used in several alignment procedures.

Rough polar alignment using the latitude scale of your scope is identical to the procedure used in the northern hemisphere.

Either look on a map, use Google Earth, or consult an almanac to find your observing site's latitude. Unlock any latitude adjustment screws on the sides of the mount and turn the latitude adjustment screws until the index on the polar axis reads your latitude. Tighten the adjustment screws if needed to secure the latitude setting. (You may also need to loosen the center pivot bolt by turning the hex nut to allow the equatorial mount head to be tilted.)

Latitude adjustment of the mount

Latitude adjustment of the mount

Now complete the polar alignment by turning the entire mount (not either axis; both should be clamped tightly) to align the upwards end of the polar axis with south on the horizon.

Another more accurate rough method is to point to Sigma Octantis. This star is located only one degree from the SCP, the point in the sky around which all the other stars appear to rotate, and where the polar axis of a properly aligned equatorial mount should point.

First, set up the mount so that the polar axis is pointing south.

Second, unlock the declination clamp and move the scope in declination so that the tube is parallel to the polar axis. Your declination setting circles should read 90° in this orientation. Clamp the declination lock.

Note: These last steps involve moving the entire mount. Don't use either the RA or Dec motions to change the position of the tube.

Move the mount in altitude and azimuth until Sigma Octantis is in your finder's field of view or centered in your finderscope. At magnitude 5.5, it is a fainter star--just slightly brighter than the unaided eye limit--so your finder will definitely be helpful here.

Vicinity of south celestial pole

Sigma Octantis and the SCP

Tweak the position of the mount by again moving the mount, this time centering Sigma in the eyepiece field of view. Altitude can be adjusted using the latitude adjustment screw or shortening-lengthening tripod legs.

For greater accuracy, you can point directly at the SCP using an offset from Sigma Octantis. (This can be done after aligning the optical axis of your finderscope with the polar axis.) Use the chart above or these patterns of southern circumpolar stars to find the SCP. Draw an imaginary line toward the SCP through the Southern Cross stars Gamma Crucis and Alpha Crucis (down the long axis of the cross). Draw another imaginary line toward the SCP at a right angle to a line connecting Alpha Centauri and Beta Centauri. The intersection of these two imaginary lines will point you close to the south celestial pole.

Via Celestron

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    $\begingroup$ The drift method certainly is precise, but I feel the answer is incomplete without a less precise but much quicker method. I am not familiar with polar alignment in the South so I can't provide an answer. Is there any method similar to using a polar scope with Polaris that would work in the South? $\endgroup$ – Florin Andrei May 8 '18 at 22:28
  • $\begingroup$ @FlorinAndrei great point, duly edited $\endgroup$ – Jonathan Landrum May 9 '18 at 15:06
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Okay so firstly your telescope would never work if you point in to the north(as you are in the southern hemisphere)

Why dont you look these links up? They completely answer your question and more.

https://www.youtube.com/watch?v=35E9Lqjypz8

https://www.youtube.com/watch?v=35E9Lqjypz8

http://www.celestron.com/support/knowledgebase/articles/how-do-i-polar-align-my-telescope-if-im-in-the-southern-hemisphere

Now here I assume a basic level of telescope familiarity, if you still need more help, pls feel free to comment or downvote:)

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    $\begingroup$ It might improve your answer if you could pull some of the information from those links and present them here. Link only answers are generally frowned upon since the links may break in the future, making your answer not useful. $\endgroup$ – zephyr Mar 16 '17 at 14:27
  • $\begingroup$ @zephyr I am new to this site and I am unable to quote a webpage. $\endgroup$ – Agile_Eagle Mar 17 '17 at 4:47

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