Meade's #777 Off-Axis Guider provides a means during long-exposure astrophotography for the photographer to monitor the tracking of the telescope, assuring that the telescope remains precisely positioned upon the object being photographed.
Like a T-Adapter, the #777 Off-Axis Guider couples the camera body to the telescope in a straight-through path. But unlike common t-mount adapters, it also diverts a small amount of the incoming light to be diverted at a right angle, allowing a star's position to be examined for tracking errors when compared with a known position upon an illuminated reticle eyepiece at the beginning of the exposure. Position corrections can then be effected using the telescope's hand controller or drive corrector.
- Works with Many Telescopes with 2"-18 Threaded Rear Cells
- The knurled slip ring attaches directly upon 2.00"-18 threaded rear cells of Celestron's 5.0-14.0" Schmidt-Cassegrains or Meade's 8.0-16.0" Schmidt-Cassegrains and 7.0" Maksutov-Cassegrain(Maksutov application requires extremely long exposures).
- Select Guide Star of Your Choice
- Slip ring allows 360° of guider body(telescope focuser can occasionally cause interference)
- Causes Minor Vignetting with the Corners of 35mm-Type SLR Camera Imaging Area
- Due to the design limitations, expect very minor vignetting of the extreme corners of film 35mm SLRs and full-frame digital SLRs(such as Canon 1Ds series); APS-C type digital SLRs will not exhibit such vignetting.
- Requires Camera-Specific T-Mount Adapter & Illuminated Reticle Eyepiece or CCD Autoguider
- The #777 Off-Axis Guider requires an optional T-ring to fit your particular 35mm-type camera, as well as an illuminated reticle 1.25" eyepiece or a CCD autoguider(listed here as optional accessories).