The EdgeHD .7x Focal Reducer Lens makes your EdgeHD 800 one full f-stop faster than f/10, doubling the equivalent exposure at f/10. 4-element lens design. Maintains similar flat-field performance as native EdgeHD optical design
The Explore Scientific 3in 0.7x Reducer - Corrector reduces the effective focal length of a particular instrument by the factor 0.7x (for f/8) and 0.8x (for f/10) respectively. The reducer/corrector not only reduces the focal length but also operates as a very effective field flattener.