Takahashi FC-35 0.66x Reducer with CA 100 Ring

Takahashi FC-35 0.66x Reducer with CA 100 Ring
Item # TK-TKA-19580
2 Questions(s)

Special Order

  • This Takahashi FC-35 .66X Focal Reducer comes with a CA 100 Ring and is compatible with the FC-100DF, the FS-102, and the FC-100 refractors.
  • The Tak FC-35 reduces the focal length by 10%, providing a focal length of f/4.9 for the FC-100DF, and f/5.3 for either the FC-100 or FS-102.
  • The metal back, measured from the flat rear-most shoulder of the FC-35, is 78.1 mm, and the image circle produced is 44 mm in diameter.


Takahashi FC-35 .66X Reducer
for FC-100DF, FS-102 & FC-100 Telescopes

The FC-35 0.66 X Reducer was designed by Takahashi Japan for a wide variety of their FC and FS series telescopes. This FC-35 comes with a dedicated CA 100 Ring, and is compatible with the FC-100DF, FC-100, and the FS-102. A FC-35 with CA 130 Ring is also available for the FC-125, FC-128 and FC-152. The only difference between the two models is the size of the included CA Ring.

The FC-35 will reduce the focal length of your telescope by 10%, and will provide a 44 mm diameter image circle. The metal back, as measured from the flat, rear-most shoulder of the FC-35, is 78.1 mm. With the FC-35 installed, each compatible telescope will have the following focal length and f/ratio:

  • FC-100DF: 485 mm, f/4.9
  • FC-100: 526 mm, f/5.3
  • FS-102: 542 mm, f/5.3
Additional Information

Additional Information

SKU TK-TKA-19580
Manufacturer Takahashi
Barrel Size Thread-on
Warranty 1 Year Warranty
Included Items

Included Items

  • FC-35 Reducer
  • CA 100 Ring
Questions & Answers

Product Questions

What is the spacer requirement; how many MM from back to CCD?
I have tried imaging with the DF using a Sony A6000 (APSC) and do not like the results. I guess using this reducer would require me to use the Sony A7RII full frame sensor. I would like to see samples first.
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