Celestron instruction manual Collimating the StarSeeker 114mm, Collimating the StarSeeker 130mm

how to adjust the screw pairs to center the dot of the collimat- ing cap in the ring of the primary mirror mark. Once the dot is centered in the ring, the telescope is collimated, and the rear cover plate can be reinstalled on the back of the mirror cell.

Figure 6-1.The view of a collimated telescope as seen through the focuser of the StarSeeker 114mm and 130mm reflectors.

NOTE: The center ring sticker need not ever be removed from the primary mirror. Because it lies directly in the shadow of the secondary mirror, its presence in no way adversely affects the optical performance of the telescope or the image quality. That might seem counter-intuitive, but it’s true!

Collimating the StarSeeker 114mm

Adjustments to the collimation of the telescope can be made by turning the collimation adjustment knobs located at the rear of the optical tube (Figure 6-2). First loosen the three Phillips head screws on the rear cell of the tube. Turn each collimation knob, one at a time, until the reflected image of the collimating cap’s dot in the secondary mirror is centered in the primary mirror center mark ring. Once the telescope is col- limated, tighten the Phillips head screws until you feel a slight resistance. Do not over tighten the screws.

Collimating the StarSeeker 130mm

To perform collimation adjustments, the rear cover plate must first be removed. This is done by unthreading the three small Phillips-head screws on the back of the mirror cell (Figure 6-3). Once the cover plate is removed, the collimation adjust- ment screws are accessible (Figure 6-4).

Collimation adjustments are made by adjusting the three pairs of collimation screws (Figure 6-4). The collimation screws can be turned with a Phillips head screwdriver and a 2.5mm hex key. Each pair of collimation screws work together to adjust the alignment of the primary mirror; one screw must be loosened and the other tightened by the same amount. Try tighten- ing and loosening one of the pairs of collimation screws by one turn. Look into the focuser to see if the secondary mirror reflection has moved closer to the center of the primary mirror reflection. The collimating cap makes this easy to see; watch if the “dot” of the collimating cap is moving closer or farther away from the ring on the center of the primary mirror. Repeat this process on the other two pairs of collimation screws, if necessary. It will take a little trial and error to get a feel for

Support screws

Collimation screws

Figure 6-2.Collimation adjustment screws for the StarSeeker 114mm and 130mm.

Rear cover plate Collimation screw pairs

Figure 6-3.To access the	Figure 6-4. Collimation
collimation adjustment screws,	adjusted by tightening and
the rear cover plate must first	loosening each pair of screws.
be removed.

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