Askar 111F 0.74× Reducer

Product introduction The 0.74× reducer brings the Askar 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 Askar 111F 0.74× 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 M68×1 threads for optimal adaptability and stability. The 111F photographic extension tube includes M54×0.75 and M48×0.75 adapters, allowing for direct and convenient connection to the 111F 0.74× reducer. The reducer’s rear adapter ring features a built-in M48×0.75 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. Specifications Parameter （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 M68*1 Size Diagram Installation Optical Path Diagram Spot Diagram