Takahashi TOA130R Reducer

Takahashi TOA130R Reducer
Item # TK-TOA130R
  • The Takahashi TOA Reducer was designed for 2.7"/4" TOA-130 models.
  • Transform your TOA into a f/5.76 system!
  • The Takahashi TOA-130 RD Reducer is also compatible with the FS-102 NSV.
  • Produces a flat field for your CCD/35mm imaging needs with a 50mm circle.


Takahashi TOA-130 RD Reducer

The Takahashi TOA-130 RD Reducer is ready to make your Takahashi TOA-130 turn into the fast focal ratio you want for your most demanding astrophotography needs. Just put this focal reducer into place on either the 2.7" or 4" focuser and instantly transform your system into an f/5.76!

The Takahashi TOA130R Focal Reducer measures 2.7" in diameter and was designed with 35mm photography and large chip CCD astrophotography (35mm format) in mind. It fits focuser of all 2.7" focuser TOA-130 optical tube assemblies as well as the Takahashi FS-102, FS-128, TSA-102S. With the addition of a 4" to 2.7" adapter, the Takahashi TOA130R Focal Reducer is also compatible with the 4" focuser focuser design of the Takahashi TOA-130 and 150. The TOA130R is fully threaded to match all accessories.

How does the Takahashi TOA130R Focal Reducer work? Like all Takahashi optics, it begins with high quality, fully multicoated glass and changes the focal length of an f/8 to f/6 - even on older model telescope. At the same time, it also produces a flat field image, fully unvignetted, and will crisp, perfect stars to right out to the edge of space. As a finishing touch, Takahashi has also provided fully threaded metal covers to help protect both threads and optics!

Takahashi Product Number: TOA130R
Additional Information

Additional Information

Manufacturer Takahashi
Barrel Size 4"
Warranty 5 Year Warranty

Customer Reviews 2 item(s)

Useful for medium sized detectors
This reducer/flattener is useful up to the (nowdays medium sized detectors that are full frame 35mm size (~43mm diagonal dimension. Vignetting becomes rather severe for any larger detector. It does not reduce vignetting compared to using the scope without it (a previous review is incorrect in that regard, but it does improve the field flatness.

For larger detectors you must use the 67 flattener, and then you can achieve a larger actual field than is possible with this reducer.
1= Houston, We Have a Problem & 5= It's Out of This World
Review by PE / (Posted on 12/31/2012)
A must for imaging with TOA/TSA/FS scopes
This reducer is specifically matched for Takahashi's triplet TOA-130 and TSA-102 scopes but will work well on an FS-102 or FS-128 as well. This has the dual benifit of acting as a 0.75x reducer (taking the TOA-130 to f/5.7 or the TSA-102 to f/6.0 - which increases photographic speed and cuts necessary exposure times by almost 50% - and a CCD/35mm flattener yeilding an image cirlce of 50mm. For comparison, a 35mm film plane or SBIG STL-11000 CCD chip both have diagonals of 44mm, meaning that both will be flat to the corners. Depending on sky darkness and chip size, some vignetting will occur, but much less than the same scope without the reducer.
1= Houston, We Have a Problem & 5= It's Out of This World
Review by HC / (Posted on 7/18/2007)
Included Items

Included Items

  • Takahashi TOA-130 RD Reducer
Questions & Answers

Product Questions

My Tak FS-102 accessories include a TOA/FS RD focal reducer. Would greatly appreciate assistance to help me determine if 1) There is a proper or optimal objective to focal length distance where the reducer should be placed and, 2) What the distance between the reducer and camera focal plane must be? 3) Related to the second question, would the TOA to camera focal plane distance be the same as that to place an eyepiece's focal plane. The instruction sheet coming with the TOA gives three numbers: 614mm, 1:6.02, and phi - 50mm. The 614mm and 1:6.02 logically describe the new equivalent focal length and f/ratios with the TOA in place. Information gleaned from even the current ad implies the compressor provides coverage over a 50mm diameter circle at the film plane. But don't all of these, especially coma correction, depend on the proper position of the added element within the system? Placement distances must matter, even if those have an acceptable range of variation as taken into consideration in the design. I would be delighted to hear from TOA users who see what might be missing right before me! Sincerely, John Z
Support / Downloads
Related Blog Posts