Tips for Using Your “Go To” Scope

A common complaint from owners of new telescopes is, "It won't focus!" Computerized telescopes run the risk of eliciting a new complaint: "It won't aim!" Here are tips to ensure trouble-free slewing to the sky's wonders.

For Any "Go To" Telescope

  • Level the tripod by eye, then level the tube. Aim the telescope as close to true north as you can. Don't aim it at magnetic north, where a compass points.
  • Ensure that any add-on finderscope or device used to sight stars is aligned with the main optics.
  • Know the sky. Aligning on Castor when the scope is asking for Pollux just 4-1/2 degrees away will cause the telescope to point up to several eyepiece fields from your intended target.
  • If you cannot see an alignment star the scope is asking for, skip to the next star on the list. With a Meade, select the next star by hitting any direction button or the Down scroll key anytime during a slew. With a Celestron, hit any direction button to stop a slew in progress, then hit Undo. Or hit Undo once a slew has finished.
  • Try to pick stars widely separated in the sky.
Go To telescope controls
Sky & Telescope: Craig Michael Utter
  • If pointing is inaccurate in a remote region of the sky, realign on a bright star in that area. With the Meades, slew to and center the new star. Once there, hold the Enter button for 2 seconds. Then hit Enter again as instructed. With the NexStars, first center the new star in the eyepiece, then select that star under List: Named Stars. Press the Align key. The display will ask you which alignment star you want to replace. Choose the one closest to your new star and hit Enter.
  • Take care not to bump the tripod or telescope tube. Doing so will throw off your careful alignment.

For Meade ETX-ATs

  • Be sure your telescope is set for Targets: Astronomical (found in the Setup menu) in order to activate the tracking motors. The scope may not be set for this by default out of the box. Another required setting under Setup is Telescope: Mount: Altazimuth for correct tracking with the scope set up as most people will use it -- on the standard tripod or on a table.
Go To telescope controls
Sky & Telescope: Craig Michael Utter
  • An observing location may have already been entered into your telescope at the store. To check, go under Setup: Site, then hit Select to see what location the scope is programmed for. Hit Add to choose a new location if necessary.
  • Be sure the clutches are snuggly locked down. If a clutch is loose the scope will not move properly under motor control.
  • Hitting Go To after arriving at an object (or where the ETX thinks the object should be) initiates a clever "square dance"-- the telescope starts to scan around in an ever-widening search pattern, a handy way to locate an object just outside the field.
  • If you have trouble reading the scrolling text, press the Down arrow key to slow the scroll speed. The Up key speeds it up.
Autostar control: Calibrate Motors
Sky & Telescope: Craig Michael Utter
  • You may have to "Calibrate Motors" (an option found under Setup: Telescope) after slewing problems caused by low batteries. If problems persist, follow the instruction manual for the steps required to "Train" the drive.

For Celestron NexStars

  • If the altitude axis seems a little loose (as our 60GT was) be sure to balance the tube in its cradle, or the scope may not move up and down correctly.
  • Under the Menu item, be sure Tracking is set to Altazimuth and that under Model Select your telescope model is chosen (scroll to it and hit Enter if it isn't).
  • Be sure to enter the date and time in the right format (mm/dd/yy).
  • Pressing one direction button then holding down the opposite direction button accelerates a slew to full speed, a shortcut to Rate 9 speed without having to divert your eye to use the numeric keypad.
Celestron NexStar controls
Sky & Telescope: Craig Michael Utter
  • If you are not sure your intended target is above the horizon, check first by hitting the Info button, then scrolling down to the altitude readout. If it is a minus number, the scope may hit the base as it slews down, forcing you to realign.
  • Keep an eye on the telescope as it swings up to an object high overhead. If it looks as if it will hit the tripod, don't panic. Hitting any direction key stops a slew in progress and readies the telescope for a new command.