Lumicon 2" Cassegrain Easy Guider, Model LG1027

The Lumicon 2" Cassegrain Easy Guider, Model LG1027 includes all the features of the traditional Cassegrain Easy Guider for 7-9" SCTs. With this updated version, the threaded SCT attachment ring is replaced with a 2" male "nose-piece" that drops into any focuser with a 2" female output port (Note: on GOTO telescopes, check your instruction manual for setting slew limits before operating)

Over the course of a long exposure, one's telescope alignment with "celestial north" (which is the optical center in the sky about which everything seems to rotate from our point of view) becomes especially critical. When merely observing a sky object, a small variance between your telescope mount's approximation of celestial north and true celestial north matters very little; the object of interest will just veer out of the center of the eyepiece if you're off, and you'll just tweak your telescope to correct it.

But, with astrophotography, you can't see what the camera sees; otherwise, you'd be blocking the exposure. Why? Because when you hit the shutter, the mirror goes "up" and you can't see what the camera is actually recording. Thus, you must be absolutely certain that the objects aren't drifting, and the best way to do that is to observe a small portion of the telescope's field of view (seen by the scope, but not by the camera attached to the scope) and align a reticle with a registration point (i.e. one particular star).

The Guider cuts off a slice of the field, enlarges it through the prism and allows you to pinpoint a registration point in space. As the object appears to "drift", the Guider permits you to re-align the object in the reticle, thereby, keeping the image sharp for your exposure.

The Cassegrain Easy Guider comes with a filter compartment which is conveniently located behind the prism. The advantage of this configuration is that you can zero in on your target without the visual strain of having to adjust through the filtration. However, only your camera receives the filtered light.

Note! The following accessories are required for photography: A prism diagonal; a guiding eyepiece (or auto-guider); and a camera-specific T-ring.