How do you focus a SCT?
All Celestron SCTs and some Maks adjust focus by sliding the primary mirror along a set of nesting baffles inside the main tube. This is done by an arm to one side of the tube that is fixed to the mirror. Because of this design, some lateral shift may occur as you focus the scope.
What is a feather touch focuser?
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How does a SCT telescope focus?
The focusing knob of an SCT is located off to the side of the primary mirror, and as it’s turned a rod pushes the mirror near its edge to displace it. However, the mirror itself is held near its center on a long baffle tube. So when the knob is turned, the mirror tilts slightly.
What is mirror flop on an SCT?
Mirror flop is movement in the primary mirror that occurs as the optical tube is aimed in different directions on the mount. As the mirror moves so does the image which is ‘image shift’. In my experience SCT designed telescopes are more susceptible to mirror flop.
How do you focus a Cassegrain telescope?
The focusing knob, which moves the primary mirror, is on the rear cell of the telescope just below the star diagonal and eyepiece. Turn the focusing knob until the image is sharp. If the knob will not turn, it has reached the end of its travel on the focusing mechanism.
How do you calibrate a Celestron focuser?
To calibrate using a Celestron hand control, press the MENU button, then select “Focuser,” then “Calibration.” If using either the Celestron Focuser Utility Program or Celestron PWI software, calibration can be done directly from the program’s user interface.
What is mirror flop?
Mirror flop is movement in the primary mirror that occurs as the optical tube is aimed in different directions on the mount. As the mirror moves so does the image which is ‘image shift’.
What is an image shift?
Image shifting is simply shifting each pixel of the image to a new position. This is a method of pixel shift used in digital cameras to produce super-resolution images.
How do you lock a SCT mirror?
To lock the focuser after focusing in the normal manner, tighten the focus lock knob until the focus knob does not rotate. Do not use excessive force! When imaging, use a Borg focuser in conjunction with the SCT focuser lock.