Takahashi 76D RD TKA18580 reducer, with an M56x0.75 female input, an M52x0.75 male output, and a mechanical back focus of 56.2 mm.
CHF 436.40incl. Swiss VAT
Part Number TKA18580
The Takahashi 76D RD is a focal reducer designed for certain FC-series refractors. This part number, TKA18580, corresponds to the 76D RD listed in the manufacturer’s specifications, not to a kit that includes a telescope or a camera. It is of interest to photographers who are building an optical system around a compatible instrument and wish to incorporate a reducer suited to this series.
The Takahashi data sheet specifically lists the FC-76DC, FC-76DS, FC-100DF, and FC-100DZ. It highlights the benefits of this reducer for instruments equipped with a compact focusing system, comparable to that of the FS-60CB. This comparison describes the mechanical system; it is not sufficient to add the FS-60CB to the list of compatible instruments. Before assembling the setup, check the diagram for your exact telescope model and the necessary adapter rings.
The input uses an M56x0.75 female thread; the output is M52x0.75 male. The specified mechanical backfocus is 56.2 mm. These specifications allow you to prepare the adapters and sensor spacing without confusing the thread diameter with the pipe diameter. Takahashi describes connecting a camera body using a wide-field T-ring for the FS-60, selected according to the camera brand. A CMOS or CCD camera may also be used, with or without a filter wheel, provided the required mounting and focal length are observed.
The body is 48 mm long and weighs 190 g. The manufacturer’s specifications list a corrected image circle as «30 mm/36 mm,» without specifying which value corresponds to a particular mount. It would therefore be misleading to promise the same field of view with all the eyepieces listed. Similarly, no single reduction factor or resulting focal length is specified in this data sheet: these values must be determined for the specific configuration chosen.
| Features | Value |
|---|---|
| Reference | TKA18580 |
| Corrected image circle | 30 mm/36 mm (configuration not specified in the source) |
| Mechanical Input Interface | M56x0.75 female thread |
| Mechanical Output Interface | M52x0.75 male thread |
| Mechanical backfocus | 56.2 mm |
| Length | 48 mm |
| Weight | 190 g |
76D RD reducer, part number TKA18580. The T-ring, housing, camera, and filter wheel mentioned here are examples of possible configurations; their inclusion is not specified in the manufacturer's data sheet.
