Astromania High Deluxe Off-Axis Guider for Astrophotography Astromania's High Deluxe Off-Axis Guider (OAG) allows simultaneous imaging and guiding through the same telescope. Features prism tilt adjustment and more than 100 degrees of radial adjustment for easy guide star. Compatible with astrophotography autoguiders that feature T-threads or a 1.25 nosepiece, as well. Eliminates tracking problems caused by using a separate guide scope such as differential flexure. Attaches to any 2 telescope focuser via the included 2 nosepiece, or onto any T-thread equipped.