Takahashi FSQ-106EDX4 106mm (4.2") Quadruplet Apochromat Optical Tube Assembly (OTA)

Takahashi FSQ-106EDX4 106mm (4.2") Quadruplet Apochromat Optical Tube Assembly (OTA)

Due to high demand and global product shortages due to the pandemic, please call for availability.

The New “Q” is the redesigned flat-field super quadruplet successor to the very popular FSQ-106.

The ultra heavy duty, massive, 102mm diameter (4") focuser features an anti-torquing drawtube. The focuser is loaded with ball bearings to prevent undesired torquing (rotation of the draw tube) with heavy instruments attached. Generous back focus of 178mm allows the user to attach a variety of imaging packages, bino viewers, 2" diagonals and many other accessories.

The new camera angle adjuster/rotator will carry a 5kg (11 lbs) load and thus is able to handle the new large-chip CCD cameras. The 88mmø image circle produced by the new “Q” is 9.5° in diameter. The newly designed Takahashi micro edge focuser is included for precise control.

The tube length of 42.4cm (16.7") allows the new “Q” to be highly airline transportable. Even when the lens shade is extended the total length is only 52cm (20.5").

The new optional reducer changes the focal ratio to f/3.6 for wide field imaging produces a 6.5° field over a 44mmø image circle.

The redesigned and modified quadruplet double ED Petzval optics have been optimized for imaging as well as visual applications.

Color correction has been extended to 1000nm to produce non-bloated imaged stars.

Note: Takahashi optical tubes are sold without tube holder (rings), finderscope, star diagonal, eyepiece, reducer, extender, mount and tripod. These extra items are sold separately.

Shipping Notice: These high-precision scopes must be shipped by air for the full warranty to apply. Air shipping charges are not included in our price, and will be added to your bill. We would be happy to quote shipping charges.


  • Newly designed quadruplet Apochromat using two premium ED elements
  • Wonderfully flat field
  • Excellent color correction, produces color-free images
  • Extended color correction from near Ultraviolet to near Infrared reduces bloated star appearance when imaging
  • Airline portable less than 17" long and weighs 15 lbs
  • Ultra duty micro edge focuser with integrated fine adjustment for stable focusing, accommodates heavy CCD cameras or bino viewers
  • Enhanced back focus of 178mm (7") allows the use of any bino viewer with ease
  • Quick release finder bracket allows the user to keep finder alignment when finder is removed and reattached
  • Knife edge baffles and over sized tube produce very high contrast images


  • Aperture: 106mm (4.2")
  • Focal Length: 530mm (20.9")
  • Focal Ratio: f/5
  • Objective: New design quadruplet apochromat, Petzval design
  • Focuser Size: 102mm (4")
  • Back Focus: 178mm (7")
  • Image Circle Diameter: 88mm (3.5")
  • Photographic Field: 9.4°
  • Main Tube Diameter: 125mm (4.9")
  • Length: 424mm (16.7") (lens shade collapsed)
  • Weight: 6.8kg (15lbs)
  • Packing: triple carton (maximum protection)
  • Five year manufacturer warranty

Optional Reducer QE .73x

  • Focal Ratio: f/3.6
  • Focal Length: 387mm (15.2")
  • Image Circle Diameter: 44mm (1.7")
  • Photographic Field: 6°
  • Sold separately

Optional Extender QE

  • Focal Ratio: f/3.6
  • Focal Length: 850mm (33.5")
  • Image Circle Diameter: 44mm (1.7")
  • Photographic Field: 3°
  • Sold separately