The Askar 0.74x focal reducer for the 111F APO is a dedicated reducer-corrector designed specifically for the Askar 111F Flat-Field telescope. It shortens the system focal length to 566 mm and changes the focal ratio to f/5.1, providing a wider field of view and shorter exposure times for deep-sky astrophotography. The reducer’s optical system maintains field correction and supports a 44 mm image circle suitable for full-frame sensors.
Key features
• dedicated 0.74x focal reducer for the Askar 111F Flat-Field telescope • reduces the focal length of the Askar 111F to 566 mm • changes the system focal ratio to f/5.1 • provides a wider field of view and shorter exposure times • triplet optical design • flat-field correction for astrophotography • 44 mm image circle suitable for full-frame cameras • 55 mm backfocus from the base of the M48 male thread • M68 × 1 thread on both sides of the reducer • rear adapter with M48 × 0.75 filter thread for 2" filters • direct connection to the 111F photographic extension tube • precision CNC-machined housing • front and rear metal threaded protective caps • convex front lens - avoid touching it during installation
Kit contents
• Askar 0.74x focal reducer for 111F • front metal threaded protective cap • rear metal threaded protective cap
Technical parameters
• manufacturer: Askar • model: 111F 0.74× Reducer • accessory type: focal reducer / field corrector • compatibility: Askar 111F Flat-Field • reduction factor: 0.74x • resulting focal length with Askar 111F: 566 mm • resulting focal ratio with Askar 111F: f/5.1 • optical design: triplet • image circle: 44 mm • full-frame support: yes • backfocus: 55 mm from the base of the M48 male thread • front thread: M68 × 1 • rear thread: M68 × 1 • filter thread: M48 × 0.75 / 2" • outside diameter: 72 mm • mechanical length: 80 mm • weight: 0.5 kg
The Askar 0.74x reducer for the 111F turns the Askar 111F into a faster astrograph with a wider field of view while preserving the field correction required for full-frame imaging.
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