To get the best performance from your Schmidt-Cassegrain (SCT) or EdgeHD telescope, its optics must be collimated—properly aligned within the telescope.
How do you know if collimation is SCT?
Celestron SCTs use 3 small Phillips or hex head screws for adjustment. Some optical tubes hide the screws under a cover that you can easily pry off with a fingernail. For Fastar-equipped SCTs, turn the triangular cover plate either clockwise or counterclockwise to reveal the collimation screws.
How do I know if my telescope needs collimation?
You want to see a diffraction pattern of concentric circles appear around it. Basically, this refers to circles around the star that might look a little wiggly. If the circles you see are not concentric, then your telescope needs to be collimated.
What is a collimation cap?
Option #2: Collimation Cap The device is simply a plastic cap with a small hole in its centre and a reflective underside. If your telescope didn’t come with one, you can make one with an old plastic film canister. For 90% of the collimation I do, this is the tool that I use.
How do I know if I need to collimate my telescope?
Does my telescope need collimation?
To do it, you’ll need a dark sky, a bright star in it, and your telescope! With your telescope, focus on a star that’s very bright, such as Sirius. Basically, this refers to circles around the star that might look a little wiggly. If the circles you see are not concentric, then your telescope needs to be collimated.
Do you need a collimation cap?
For most people, a simple collimation cap is fine. For collimation I use either a Cheshire or laser to position the secondary mirror (something that rarely needs adjustment) and a simple collimation cap for tweaking the primary. That’s it.
How do you collimate a Chesire telescope?
To collimate the telescope it should be aimed towards a bright but not glaring surface such as a well lit pale painted wall or fabric in order to get a good image in the telescope and the Chesire should be arranged so that its shiny angled surface gets a good light.
How do I adjust the collimation on my SCT?
Celestron SCTs use 3 small Phillips or hex head screws for adjustment. Some optical tubes hide the screws under a cover that you can easily pry off with a fingernail. For Fastar-equipped SCTs, turn the triangular cover plate either clockwise or counterclockwise to reveal the collimation screws.
How do I know if my scope is collimation or collimation?
Turn the screws by only 1/6 to 1/8 turn adjustments, Each time you make an adjustment the star will move in the field of view, and you’ll need to re-center the star to check if the scope is in collimation. Out-of-collimation SCT showing star going from inside to outside of focus.
How do you remove the collimation screw from a telescope?
These three screws are clearly visible when looking at the front of most telescopes (see Figure 6 ). Some older SCT telescopes have an orange cap that covers the collimation screws (see Figure 7 ). Carefully use a fl at-head instrument or other tool to pry the cap off.
