Astro-Physics CCD Focal Reducer

This reducer effectively shortens your telescope's focal length, which allows for faster imaging. By reducing your focal ratio, you can capture celestial images with significantly shorter exposure times.

The compression ratio depends on your specific imaging setup. You will get a 0.67x ratio when using a filter wheel with your camera, and a 0.75x ratio when imaging without one.

This unit is specifically designed for refractor telescopes with focal ratios between f/9 and f/18. It is not intended for use with other telescope designs.

Back focus is the distance from the back of the reducer to your camera's sensor. You must ensure your imaging train—including any adapters, filter wheels, and the camera itself—allows for exactly 5 inches of spacing to achieve proper focus and image quality.

While this reducer is optimized for SBIG ST7, ST8, and ST10 cameras, it is designed to work within the constraints of those specific models. Using it with other cameras may result in performance issues or difficulty reaching focus.

It is designed for convenience and connects directly to any standard 2-inch telescope nosepiece, making it a straightforward addition to your existing imaging train.