Dobsonian Guide and Checklist


  • Aperture: 356mm
  • Focal Length: 1650mm
  • Focal Ratio: f/4.6

Opening the scope shelter:

  1. Log in.
  2. Remove the padlocks and carabiners from the corners of the shelter.  Immediately return the keys to the key lockbox.  (Place the locks and carabiners where you will not lose them in the dark!)
  3. Fold the lock latches flat on the deck to avoid a tripping hazard.
  4. Tip the shelter up from the south end and gently roll it to the north on the north-end casters. Make sure it is far enough away that it will not interfere with observing.
  5. Remove the soft cover from the telescope without disturbing its position (this will keep it from becoming too badly misaligned). It has a drawstring that is cinched around the base to keep bugs and mice out.  Put the soft cover on top of the shelter.
  6. Remove the covers from the mirror box, the business end of the scope, the focuser and the secondary mirror cover and place them under the shelter so they don’t collect dew.
  7. Get the silver step stool from the interior east wall of the refractor building. You will need it for observing high overhead.


  1. There is a 120V to 12V adaptor on the base of the telescope. Plug it into the outlet next to the base.  Make sure it is connected by noting the light.
  2. Flip the power switch on. If the hand controller does not light up, jiggle all the contacts. Go through the menu on the hand controller, entering time, location, etc. (The scope usually remembers everything except the local time.) The coordinates for RRO are 34° 56’ 47.2” N, 92° 34’ 18.2” W (Decimal: 34.946441 -92.571707).  Use local time and set time zone to -6 as it will separately as if the time is DLS or Std. Time.
  3. Adjust the clutches on the Vertical and Horizontal Axis.  If you intend to only move the scope by slewing it using the hand paddle, this is not critical as long as the clutches are snug enough not to allow slippage.  If you wish to slew the scope manually you don’t want the clutches to be too tight.  Loosen each one and then just barely snug them up.  You should be able to move the scope easily and smoothly but with noticeable drag.
  4. Skip the Brightstar Alignment and select the Two Star procedure.  Select a star from the offered list to begin the alignment then slew the scope and align the star in the center FOV.  You can do this by manually pushing the scope or buy using the slew buttons on the controller.  (If you don’t seem to get a response from the controller slew buttons change the slew rate to a higher speed.)  (You don’t have to use the reticle eyepiece to aligned well enough.) Once centered confirm the sync then choose a second star reasonably distant from the first, but on the same side of the meridian.  This time the scope will slew to the approximate location.  Again center the second star and sync.  You are done. (If moving the scope manually is stiff or jerky loosen the tension brake on the Altitude axis.)
  6. To use the 2-inch eyepieces, loosen the two larger diameter thumbscrews on the focuser barrel and remove the 1.25-inch adaptor.
  7. Watch out for power CORD WRAP! If the scope turns more than one revolution in the same direction, the power cord will be pulled out of the socket.


There is a red light fixture that will illuminate the deck. The all-weather switch box for it is on the east side of the exterior of the refractor building within reach from the deck at about shoulder height.

  1. Replace the 1.25-inch adapter and the focuser cap.
  2. Replace the secondary mirror cover. (this is easy to forget!)
  3. Replace the large rigid plastic cover on the end of the telescope.
  4. Replace the large rigid plastic cover over the mirror housing (use the one with the Velcro strips on it.
  5. Move the telescope tube to the horizontal position, pointed north.  You can do this by hand, or by selecting the park option.
  6. If you moved it by hand, tighten the clutches on the west side to keep the scope in position, and use the hand controller “utilities” menu to park the telescope in the “current” position. Refer to the manual for this procedure if necessary.
  7. Once parked, turn the power switch off, unplug the power adaptor and place it on the base. 
  8. Gently slide the soft cover over the telescope and stuff the open edge of it between the scope base and the deck. Pull the drawstring tight around the base to keep bugs and animals outside of the soft cover.
  9. Replace the shelter.  Carefully move the cover until the north end is roughly lined up with the locks on the deck. Gently let the cover down over the telescope.
  10. Align the locks may take some patience, but get them all roughly aligned, then attach one, then the cattycornered one and the others will fall in place.  Place the two locks and the two carabiners cattycorner to one another.  DO NOT lock the padlocks before all four hasps and staples are lined up.
  11. Report any problems encountered


  1. Return the eyepieces, accessories, and manual to the case and place it back in the refractor building.
  2. Using the red deck light, check for any items left out.
  3. If not already done, place the keys back in the lockbox and follow the usual procedure for shutting down the site and locking up.