- Description
- Specifications
- Downloads
Product Overview
The SD Ring is the spacing adapter Takahashi publishes for fitting the FC/FS Multi-Flattener 1.04x to the FS-60C. It threads M55.9 x 0.75 and adds a 17.5 mm light path — the figures Takahashi lists in its accessory ring table for this part.
Who It's For
This is what you need if you own an FS-60C and are setting up the FC/FS Multi-Flattener 1.04x for imaging. It is a spacing part, not a standalone accessory.
Key Features & Design
- M55.9 x 0.75 thread: the interface Takahashi publishes for this ring.
- 17.5 mm light path: the length it adds to the imaging train ahead of the flattener.
- Purpose-built for the FS-60C: distinct from the CA-60C ring used on the FS-60CB.
Recommended Uses
- Imaging setup on the FS-60C with the FC/FS Multi-Flattener 1.04x.
Compatibility and Accessory Notes
Takahashi's own accessory ring table notes that the SD Ring cannot be threaded onto the female port of the Camera Angle Adjuster S — the same restriction applies to the M55.9 Extension Tube L30. If your train includes the Camera Angle Adjuster S, check the fit with us before ordering. Full spacing figures for the FC and FS line are in the Takahashi Back Focus Guide.
Good to Know Before You Order
- It does not work alone. The SD Ring only sets spacing for the Multi-Flattener 1.04x on the FS-60C — the flattener itself is a separate purchase.
- Not for use with the Camera Angle Adjuster S — Takahashi's own documentation flags this combination as incompatible. If that is part of your train, send us the details and we will confirm an alternative.
Frequently Asked Questions
Is it difficult to set up?
No — it threads directly into the imaging train ahead of the flattener at the published M55.9 x 0.75 interface.
Is this the same as the CA-60C ring?
No. The CA-60C is matched to the FS-60CB; the SD Ring is the part Takahashi publishes for the FS-60C.
Can I use it with the Camera Angle Adjuster S?
Takahashi's documentation says no — the thread will not engage the Camera Angle Adjuster S's female port. Send us your setup and we will work out the right combination.
Bottom Line
In short: an M55.9 x 0.75, 17.5 mm spacing ring that sets up the FC/FS Multi-Flattener 1.04x correctly on the FS-60C.
| Type | Field flattener spacer ring |
|---|---|
| Compatible telescope | FS-60C |
| Used with | FC/FS Multi-Flattener 1.04x (TKA00582) |
| Thread | M55.9 x 0.75 |
| Light path length | 17.5 mm |
| Compatibility note | Cannot be threaded onto the female port of the Camera Angle Adjuster S |
Shopping Guide
- Takahashi English Catalog 2025 — PDF, 8.63 MB
System Charts, Diagrams and Adapter Guides
- Takahashi Telescope Backfocus Table — PDF, 71 kB
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