What is the total back focus of the Indigo OAG with Helical Focuser?
The Indigo OAG itself has an optical thickness of 10mm. The included M54 and M48 adapters each add 4mm of thickness. Therefore, the total back focus consumed by the OAG with one adapter attached is 14mm.
How do I adjust the Indigo OAG's prism for my full-frame camera?
The 12x8mm prism is mounted on a stalk that can be moved up or down. To avoid vignetting your main sensor, loosen the setscrews on the side of the OAG body, raise the prism just enough so it sits outside the light cone of your main imaging sensor, and then retighten the screws to lock it in place. This ensures maximum illumination for both your main camera and your guide camera.
Can I use the Indigo OAG with the Pegasus Astro Indigo Filter Wheel?
Yes, the Indigo OAG is designed to bolt directly to the Indigo Filter Wheel using the 62mm through-hole pattern. This creates a solid, integrated unit. The combined back focus of the Indigo Filter Wheel (19mm) and the Indigo OAG (14mm) is 33mm.
What guide cameras are compatible with the Indigo OAG's helical focuser?
The helical focuser is designed to accept any guide camera with a standard 1.25” nosepiece. This covers the vast majority of popular planetary and guide cameras on the market.
Will the Indigo OAG work with my Celestron EdgeHD 8" telescope?
Yes. The included M54 female threaded adapter allows direct connection to many standard flatteners and reducers. For a Celestron EdgeHD 8", you would typically connect to the M48 threads on the .7x reducer or a camera adapter. The 14mm back focus of the Indigo OAG fits well within the 146mm back focus requirement of the EdgeHD optical system, leaving plenty of room for your filter wheel and camera.
What is the benefit of an Off-Axis Guider (OAG) over a separate guide scope?
An OAG uses the same light path as your main imaging camera, completely eliminating the possibility of differential flexure. This is a common problem where a separate guide scope and the main telescope flex or shift independently, causing elongated stars even with perfect guiding. The Indigo OAG ensures your guide camera sees the exact same movement your imaging camera does.