What is a Crayford style focuser?
The Crayford focuser is a simplified focusing mechanism for amateur astronomical telescopes. Instead of the rack and pinion, they have a smooth spring-loaded shaft which holds the focus tube against four opposing bearing surfaces, and controls its movement.
What does a telescope focuser do?
The focuser moves the eyepiece holder up and down slightly, adjusting the focus of the eyepiece for each individual observer. There are friction focusers or rack-and-pinion focusers. Regardless of the type on your telescope, your focuser should move smoothly without causing your telescope to shake.
How do you focus a SCT telescope?
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.
How does a SCT 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. So when the knob is turned, the mirror tilts slightly. This results in a movement of the image in the eyepiece or on the camera sensor.
How does Celestron focuser work?
The Celestron Focus Motor enables electronic focusing using a computer or Celestron computerized mount hand controller for remote/hands-free observing. Self-powering: When connected to a Celestron computerized mount, the mount provides the power. When connected directly to a computer, USB provides the power.
What is mirror flop in a telescope?
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.
