Spot diagrams

As on the FSQ-106ED, the built-in field flattener, perfectly designed and manufactured, gives an almost homogeneous flat field of 44mm diameter. At prime focus, at the edge of field (22mm from the optical axis), stars remain pinpoints, including on pixels of 7µ width. The addition of the Reducer-QE 0.73x, specifically designed for this quadruplet, makes it possible to gain in field of view on the widest deep-sky objects while preserving the initial optical performances.