SHARPSTAR 150HNT User manual

Collimation of the SharpStar 150HNT
【Preparation is Required before Collimation】
Sharpstar 150 Hyperboloid Newtonian Reflector, Allen Wrench, Laser
Calibrator, Crosshair Eyepiece
Sharpstar 150 Hyperboloid Newtonian Reflector Allen Wrench
Laser Calibrator Crosshair Eyepiece
【Connection Way】

【Preparation for Collimation】
Owing to the existence of diopter in the reducer，the reducer assembly
must be removed in order to collimate the 150HNT. Put the tool with its
two sharp points into the two holes in the reducer group frame
accordingly, and then turn the tool to take the reducer group off.
Reducer Group 150 Reducer-specific Tool
【Laser Collimation】
STEP 1: Adjust how far the spider disk of the secondary mirror from the
stainless steel top-surface, great if the distance is 5mm as the three set
screws in the spider disk contact with the top-surface slightly.

SETP 2: Loosen the three
small screws and tighten
the three large screws on
the back circle.
SETP 3: Insert the laser calibrator into the 1.25” adapter.
SETP 4: A laser dot will be shown on the primary mirror. Using the
wrench and hand adjust the screws on the cross of secondary mirror to
change its position so that the dot is move to the center of the circle.

SETP 5: Next, adjust the three set screws on the cross of secondary
mirror to center the laser dot on the black circle, and pre-tighten them to
hold the secondary mirror (from slightly contact in Step 1).
SETP 6: It then becomes necessary to loosen the three large screws to
further center the dot, and tighten the three small screws to hold this
adjustment. Note the location of the red dot in relation to the black circle
or the location of the feedback red dot provided by laser calibrator in
relation to the central hole in the process of observing.

SETP 7: Because the short focal ratio can lead to a more sensitive light
axis, and thus the adjusted axis in Step 6 may be offset again in the
process of tightening the small screws on the back circle. Now further
fine adjustment is required to re-center the dot.
SETP 8: Put the reducer group back into the focusing barrel.
【Crosshair Eyepiece Collimation】
See STEP 1 and STEP 2 in Laser Collimation, which aren't repeated
here.
STEP 3: Insert the crosshair eyepiece into the 1.25” adapter.

STEP 4: There are the circle of primary mirror, the circle of secondary
mirror, the central mark on the primary mirror, the reflection hole on the
surface of the secondary mirror and a crosshair in your field. Rotating the
secondary mirror group and using the wrench with set screws on the cross
to control the position of the secondary so that the circle of the primary
mirror is moved to be concentric with the circle of the secondary mirror
as seen through the collimating eyepiece, and the center reflection of the
eyepiece is centered over the crosshair. After this is done, make certain
that the adjustment has been locked in place though tightening the set
screws.

STEP 5: It’s now necessary loosen the three large screws to center the
primary mirror mark on hole placed on the collimating eyepiece. Then
tighten the small screws.
STEP 6: Turn the focuser or the crosshair eyepiece, as seen the crosshair
of crosshair eyepiece and the crosshair of secondary mirror have the same
center. If not, adjust the three screws on the focuser until the desired
pattern is obtained and then tighten them.

STEP 7: Put the reducer group back into the focusing barrel.