ZWO FF110 APO Flat-Field Apochromatic Refractor The ZWO FF110 APO Refractor is a lightweight, compact instrument engineered for immersive visual observing and high-performance astrophotography. *Focus can be achieved within a back focus range of 42–73 mm, measured from the M54–M48 interface shoulder. Main Features Flexible Connectivity for Multiple Configurations Uniqueness 1. Four-Element Optical Design The optical design features four elements. These are fully air-spaced and apochromatic for superior results. All four elements work together to deliver a flat imaging field without the need for an additional field flattener. One ED (extra-low dispersion) glass element is incorporated to effectively reduce chromatic aberration and improve clarity. 2. 44 mm Image Circle — Full-Frame Support With a 44 mm image circle, this refractor telescope fully supports full-frame sensors and a wide range of imaging setups. It delivers sharp star fields with excellent edge-to-edge performance, ensuring consistent quality across the frame. 3. Native Flat-Field Design The FF110 APO features a native flat-field optical design, eliminating the need for an additional field flattener. No complex back focus calculations are required—simply attach your camera and start capturing once focus is achieved. This system pairs perfectly with the asiair pro for streamlined control of your astrophotography sessions. Convenient Design 4. Coarse & fine focus adjustment Equipped with a rigid 3-inch rack-and-pinion focuser, this telescope offers precise 1:10 dual-speed control. A built-in 360° rotator at the rear allows for smooth and accurate camera angle adjustments for perfect framing. 5. Retractable Dew Shield The telescope features a retractable dew shield, reducing overall length for improved portability during transport. Precision CNC machining and a high-quality finish, combined with internal anti-reflection coating, minimize stray light. 6. Quick-Release Mounting Rings The mounting rings are detachable, allowing for quick and easy setup or teardown of the telescope in the field. 7. Photography Extension Tube The FF110 APO includes a photography extension tube with a 2-inch filter thread and standard rear adapters. Supported standards include M48×0.75 and M54×0.75, allowing for easy integration with many imaging accessories. Performance Optical Layout Star Field Map Product Diagram Technical Specifications In the Box Warranty ZWO 2-Years Warranty