Introduction:
- The 0.74X reducer brings the 111F's focal ratio down to F5.1, delivering a faster optical system while incorporating built-in field-flattening correction to effectively eliminate field curvature - ensuring sharp and clear stars from the center to the very edges of the frame. The shorter focal ratio provides a wider field of view and shorter exposure times, making it particularly well-suited for capturing expansive nebulae, star clusters, and faint or fast-moving celestial objects.
- The 111F 0.74X Reducer features a triplet optical design and supports a 44mm full-frame image circle. Its back focus is 55mm (measured from the M48 thread), and both ends feature M68x1 threads for optimal adaptability and stability.
- The 111F photographic extension tube includes M54x0.75 and M48x0.75 adapters, allowing for direct and convenient connection to the 111F 0.74X reducer. The reducer’s rear adapter ring features a built-in M48x0.75 standard 2-inch filter thread, enabling direct installation of various astronomical filters to accommodate different imaging needs.
- The entire reducer is precision CNC-machined and comes with front and rear metal threaded caps to protect the optics from dust when not in use.
Specification:
- (After attaching) 111F Focal length: 566mm
- (After attaching) 111F Focal ratio: f/5.1
- Lens Number: Triplet design
- Back Focus: 55mm (from the base of M48 male thread)
- Weight: 0.5kg
- Rear-end thread type: M68x1
Package Included:
- 1 x Reducer




