Aligning the DEC axis to the RA axis
This portion of the procedure will assure that the DEC axis is orthogonal
or perpendicular to the RA axis. Adjustments are made to the elevation
of the fork arms to achieve perpendicularity. You will draw a set of perpendicular
lines on a wall. Call this the target. Then using the laser you will sweep
the beam across the horizontal line of the target by rotating the scope
around its RA axis, and the vertical line or the target by rotating the
scope around the DEC axis. If the RA axis and the DEC axis are not perpendicular
the beam will stray from the vertical target line. When sweeping the beam
along the line in this procedure try to be as precise as possible. Draw
a thin line, and when lining up the beam dot on the line actually line
up the edge of the beam dot on the line. That way it is easier to determine
when the beam strays from the line.
Step 1. Place the scope tripod so that when
the scope is mounted in the ALT-AZ arrangement the front (corrector plate
end) is about one foot from a flat wall. Try to find a spot on the wall
away from a drywall joint to assure the surface is flat. Level the scope
tripod. This does not have to be exact. A rough leveling will do fine.
Mount the scope in ALT-AZ arrangement.
Step 2. Wrap a piece of tape around the laser
pen ON button to hold the button down causing the laser to be on continuously.
Then tape the laser pen to the top of the scope. If you have a mount rail
or camera mount tape the pen to it instead of directly to the OTA. This
will raise the beam above obstructions caused by the corrector plate cover
and rim.
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