The 1.0x flattener does not change the focal ratio of the telescope itself. After being attached to the Askar 185APO, it maintained a focal ratio of 7. The flattener corrects field curvature and coma, resulting in flatter field edges and finer star points.

The 1.0x flattener does not change the focal ratio of the telescope itself. After attaching it to the Askar 140APO, it still maintained a focal ratio of 7. The flattener corrects field curvature and coma, resulting in flatter field edges and finer star points.

The 1.0x flattener does not change the focal ratio of the telescope. After attaching it to the Askar 120APO, it maintained a focal ratio of 7. The reducer corrects field curvature and coma, resulting in flatter field edges and sharper star points.

The 1x flattener does not change the focal ratio of the telescope. After being attached to the Askar 103APO, it still maintained a focal length of f/6.8. The flattener corrects field curvature and coma, resulting in flatter field edges and finer star points.

76mm triplet refractor FPL53 F/5.5 Sharpstar - Focal length 418mm - Focuser 2.5 "Rack & Pinion - Complete with 0.8x corrector reducer for dedicated FullFrame. The reducer takes the aperture to F/4.5