ASKAR FMA180 objective lens features Triplet air-spaced APO design, includes two pieces of ED (extra-low dispersion) glass, providing excellent correction of chromatic aberration,which lays the foundation for high quality astrophotography and observation.
  • The reducer for Askar FMA180 also adopts APO triplet design, offering a sharp image when cooperating with the objective lens. The reducer boasts an exquisite ability to enhance the quality of sky imaging, enabling our customers to get rid of all the worries about aberrations within the field.

  • The Askar FMA180 originally has an aperture of 40mm, a focal length of 220mm and a focal ratio of f/5.5. When it goes with a specially-designed F4.5 reducer, the FMA180 will be a 180mm-focal-length and f/4.5-focal-ratio professional astrograph which maintains the best quality in either ground imaging or astrophotography.

  • In the field of amateur astronomy, it is rare to find an astrograph with a focal length less than 200mm, which is conventionally a speciality of the ordinary cameras. But the ordinary cameras are not specialized for astrophotography, so the images taken by them may not always satisfying.
    Askar FMA180, a groundbreaking optical device, can reach great sharpness as well as exactly other long-focal-length astrographs.
    FMA180 is compact with a main tube length of mere 145mm and a weight of 395g. Besides, it can also function as a quality finder or guider.
    Therefore, the standard configuration contains a pair of tube rings and a finder bracket for practical installation or attachment. The finder bracket can be divided into two parts. One is the the bracket stalk and the dovetail foot for supporting the whole bracket and the other is a dovetail plate which can be disassembled and independently attached to a tripod or other camera tripod heads with the same thread type. The dovetail plate conforms to standard ARCA-SWISS requirement and is carved with corresponding slots and holes for easy connections. The plate is also designed to realize the connection to an equatorial mount with standard Vixen dovetail base.

    The portable size enables the FMA180 to be easily attached as an ordinary camera lens and wipe off the troublesome and burdensome toil when you go on a trip to explore the universe.

    Below are FMA180 usage patterns for reference:

    Photographic Mode:
    1) Main tube + focuser + reducer + reducer connection extension tube: 180mm F4.5 sextuplet APO flat field correction astrograph lens (recommended photographic mode, product assembled)
    2) Main tube + focuser + extension tube 1 + extension tube 2+reducer connection extension tube : 220mm F5.5 triplet APO lens
    Observation Mode:
    1) Main tube + focuser + extension tube 1 + 1.25" adapter: It can be combined with 1.25" star diagonal and eyepiece for standard observation mode or finderscope mode.
    2) Main tube + focuser + extension tube 1 + extension tube 2: It can be combined with 1.25" eyepiece for visual observation mode or finderscope mode.

    Spot diagram
    Optical path diagram