Celestron Deluxe Off-Axis Guider

Catadioptric by Celestron. Details:The Off-Axis Guider is an essential astroimaging accessory for long focal length telescopes that require the most accurate guiding possible. The Celestron Off-Axis Guider uses a prism to intercept a small portion of the telescope’s focal plane ...Catadioptric by Celestron.

Details:The Off-Axis Guider is an essential astroimaging accessory for long focal length telescopes that require the most accurate guiding possible. The Celestron Off-Axis Guider uses a prism to intercept a small portion of the telescope’s focal plane (outside the field of view of the main imaging camera) to locate a guide star. Any movement seen by the guide star will be the exact same movement seen by the imaging camera.

Guiding this way will correct for tracking errors, as well as opto-mechanical errors or flexure. The result: better astroimages with pinpoint round stars. Off-Axis Guiders have been around for a long time, but typically pose three main challenges: 1 Finding a guide star from the far edges of the telescope’s focal plane can be difficult, considering the small field of view and sometimes less-than-ideal illumination.

2 Getting both imaging camera and autoguider to reach focus with one another is time consuming and sometimes requires...