Page 43 - BBC Sky at Night Beginners Guide to Astronomy - 2017 UK

WHAT TO USET TO USE
WHA

HOW TO ASSEMBLE YOUR MOUNT

Follow these steps to make sure your equatorial mount is solidly built
and won’t collapse when you fi t your telescope onto it

1. The scope and mount head sit on a 2. Place the MOUNT HEAD onto the top of 3. Screw the COUNTERWEIGHT bar into
TRIPOD. Set this up in daylight if it’s your the tripod. Line up the metal peg on the top the mount head. With the rod’s locknut
fi rst time. Adjust the height of the tripod’s of the tripod with the gap underneath the tightened against the mount, take the safety
legs so the top is level with your hips and, mount, between the azimuth lock’s two bolts. screw off the end of the bar and slide the
if there is one, fi t the central accessory tray. Secure the mount head onto the tripod by counterweights halfway up the bar, tightening
Make sure that the top is level and that the tightening the big bolt hanging from the the screws on the weights to secure them.
leg labelled ‘N’ is pointing north. underside of the tripod top. Then replace the safety screw on the end.

4. The RA axis needs to point up to the 5. Fit a SLOW MOTION CABLE onto the 6. The telescope is held in the mount head by
north celestial pole. To do this, the mount’s small D-shaped shafts on the RA and the Dec. two TUBE RINGS, which are attached to a
ALTITUDE SETTING needs to be the same axes, tightening the screw at the end of each mounting plate clamped tightly into the mount
as your local latitude. Release the front and cable to hold it in place. If using a refractor, head. Our example has a short dovetail
back bolts and tilt the mount head so that the rotate the Dec. axis so that the cable extends mounting plate with two tube rings already
pointer lines up with the right number on the to the bottom. For a refl ector, fi x the cable on attached, but yours may not be fi xed to the
altitude scale, then do the bolts up again. at the top, closest to the eyepiece. mount head. In which case, attach the rings.

7. With the tube rings open, PLACE THE 8. Slip the FINDERSCOPE into its bracket 9. BALANCE YOUR SCOPE. With the tube
TUBE IN THE RINGS, then fl ip the top half and screw this into the clamp on the telescope horizontal and the Dec. axis lock loose, slide
of the rings over the tube and screw down the tube. To align it, put a low-mag eyepiece in the tube back and forth in the rings until the
locking bolts tightly so the tube doesn’t slide the main scope’s focuser and fi nd something scope rests fl at. Then do the RA axis: with the
out. You might need an extra pair of hands like a pylon on the horizon. Then look through counterweight shaft horizontal, loosen the
to help you at this point. Remember, if you’ve the fi nderscope and adjust the screws on its lock and adjust the counterweights until the
got a refl ector the eyepiece goes at the top! bracket until the pylon is in its crosshairs. scope stays put when you let go.

skyatnightmagazine.com 2012 43