Stellarvue Reducer/Flattener for Refractors

This unit is specifically engineered and optimized for 102mm f-7 refractors, including the Stellarvue SV102 Access. While it may physically attach to other telescopes, we cannot guarantee optimal field correction or performance on different optical designs.

The 0.8X reduction effectively shortens your focal length to 571mm and speeds up your focal ratio to f-5.6. This provides a wider field of view for capturing larger deep-sky objects and allows you to gather light faster, which significantly reduces your required exposure times.

The reducer maintains a precise 55mm backfocus, which is the standard distance required for most DSLR T-rings. If your specific camera setup has a different backfocus measurement, you may need to add extension tubes to achieve the correct spacing for sharp images.

Yes, the unit features a standard 48mm thread that accommodates most 2-inch astrophotography filters. This makes it easy to integrate light pollution or narrowband filters directly into your imaging train.

Backfocus is the critical distance between the back of the reducer and your camera's sensor. Maintaining this 55mm distance is essential for the flattener to properly correct optical aberrations; if you are off by more than a millimeter or two, you may notice distorted stars in the corners of your frames.