The FSQ series of telescopes were designed with the astro-imager in mind.  Featuring a four-element lens system made with superb ED glass, the FSQ produces a virtually flat field across a large image circle.  In models other than the FSQ series, the image circle is defined as the circle in which light intensity is 60% or greater.  However, because of the outstanding performance of the FSQ series, for these models the image circle is defined as the area where star images are 30 microns or less.  In all FSQ telescopes, the light intensity across the image circle is greater than 70%. 


The FSQ-130ED is the latest addition to Takahashi’s FSQ line.  The FSQ-130ED is a fusion of features from the TOA and FSQ series.  The front elements mimic the TOA series, with three elements of ED glass that almost eliminate axial chromatic aberration and spherical aberration.  The rear elements come from the FSQ-106 design, thus eliminating astigmatism and chromatic aberration.


Through its design, the amount of light reduction across the image circle is minimal.  Out to about 44 mm, the light intensity remains 97%.  Out to 64 mm, light intensity is still a remarkable 92%.  Even out to 110-mm, the light intensity is above 78%.  This light intensity reduces vignetting and keeps stars across the field pin-point.  At prime focus the FSQ-130ED produces a 110-mm image circle with an extremely flat field. 


The FSQ-130ED has a 130-mm aperture in an f/5, 650 mm telescope.  The FSQ-130ED features a retractable dew shield, a 360-degree camera angle adjuster, and a heavy duty, 4-inch rack and pinion focuser.  The focuser comes standard with a 7:1 fine focuser reduction.  The draw tube features two racks, allowing heavy imaging trains to be used without flexure of the focusing mechanism.  The FSQ-130ED can be coupled with several reducers and extenders, including the F/3 Reducer 0.6X and the 645 “super reducer”.


Optical Tube Assembly only (mount, tripod, tube holder and finder sold separately).