Off-Axis Radial Guide (OAG) Celestron 93648
The Radial Off-Axis Guide (OAG) is an essential accessory for astrophotography with long focal length telescopes that need to have the most accurate guidance system possible. CELESTRON 's new Off-Axis Radial Guidance (OAG) uses a prism to capture a small portion of the telescope's focal plane (outside the field of view captured by the main camera with which we are taking the photograph) to locate a guide star. Any motion that the guide star makes will be the same motion that the camera will photograph. Therefore, guiding with CELESTRON 's Off-Axis Radial Guide (OAG) will correct tracking errors as well as opto-mechanical errors or bending. The end result will be better astrophotography of point stars.
Off-axis radial guides have been on the market for a long time but typically have had to overcome three challenges and have not always been successful:
Locating a guide star in the outer boundary areas of the telescope's focal plane can be difficult, considering the small field of view available and the significant reduction in illumination suffered.
Getting both the camera taking the photograph and the camera used as an autoguider to achieve focus at the same time is time consuming and sometimes requires experimentation.
Specific spacers and adapters are usually needed for your particular combination of camera, telescope and autoguider, adding cost and complexity to the system.
CELESTRON' s Off-Axis Radial Guidance (OAG) achieves these challenges by:
-Using a larger 12.5mm prism that can be adjusted to move it more towards the center of the telescope's focal plane, depending on whether or not it is of interest depending on the size of the CCD used for astrophotography. With the help ofa larger prism we can locate brighter guide stars by fully illuminating the sensor used for autoguider.
- With a high quality helical focuser, which allows to fix the orientation, it is possible to have a precise and extremely smooth focusing of the autoguider without having to keep changing its orientation.
- Including all necessary spacers and adapters for the most common configurations, including DSLR cameras, NIGHTSCAPE CCD cameras and others. The following adapters are included: SCT/EDGE HD, M48 female, M42 female (T-Thread), M48 male, M42 male (T-Thread), 3 T-thread spacers.
Technical features:
The most accurate way to guide: improved accuracy compared to using a guide tube.
12.5mm multi-coated prism with aluminized back to maximize reflectivity and illumination of the autoguider.
Fixed orientation helical focuser for easy, smooth and accurate autoguider focusing.
48mm diaphanous aperture supports Full Frame cameras without causing vignetting.
Includes adapters for distance correction of DSLR, CCD NightScape and other popular astrophotography cameras.
Ideal for Schmidt-Cassegrain and EDGE HD telescopes.
Technical Specifications:
Helical focuser travel: 8mm
Telescope connection: M42, M48 and SCT/EDGE HD T-thread
Autoguider connection: M42 T-thread and standard adapter to 1.25 "
Camera connection: M42 and M48 T-thread
Weight: 510 gr
Clear aperture: 48mm
Off-Axis Radial Guide (OAG) Celestron 93648
