Takahashi Sky-90 Short 2" Adapter 25mm

Product Overview

The Short 2" Adapter (Sky90) is Takahashi's 50.8 Adapter for the Sky-90, fitting a 2" eyepiece or camera clamp with an M55.9 x 0.75 female thread. It carries a published light path of 25 mm — the amount it contributes to your optical train, not its physical length end to end.

Who It's For

This is a good match if you own a Sky-90, FOA-60, or FC-76DS and need a 2" clamp on the camera-side thread for eyepieces or 2" imaging accessories.

Key Features & Design

• 2" compression clamp: secures via two M5 screws on the rear of the ring.
• M55.9 x 0.75 female thread: the tube-side connection published in Takahashi's catalog.
• 25 mm published light path: a fixed, known contribution to your back focus total.

Recommended Uses

Accepting 2" eyepieces, diagonals, or imaging accessories on the Sky-90, FOA-60, or FC-76DS.

Compatibility and Accessory Notes

Fits the Sky-90, FOA-60, and FC-76DS. On the FOA-60Q and FOA-60, Takahashi installs it using the TKP35001 or TKP28001 adapter rather than direct threading. A longer variant, TKA21110, is also available with a different integrated light path where more spacing is needed. The Takahashi Back Focus Guide tabulates every Takahashi adapter's light path alongside each telescope's back focus target, worth checking against the rest of your imaging train.

Good to Know Before You Order

FOA-60 and FOA-60Q need an intermediate adapter: on those two models this ring installs through the TKP35001 or TKP28001 adapter rather than threading straight onto the drawtube. Send us your exact telescope model and we will confirm which parts you need together.

Frequently Asked Questions

Is it difficult to set up?

No — it threads onto the drawtube and the 2" clamp is secured with two M5 screws, with no further adjustment.

What is it used for?

Fitting 2" eyepieces, diagonals, or camera accessories to the Sky-90, FOA-60, or FC-76DS.

Does it fit the FOA-60 directly?

On the FOA-60 and FOA-60Q it installs through the TKP35001 or TKP28001 adapter rather than threading straight on — send us your setup and we will confirm the parts you need.

Bottom Line

A 25 mm light-path, M55.9 female 2" clamp for the Sky-90, FOA-60, and FC-76DS. Confirm the FOA-60/FOA-60Q intermediate adapter with us before ordering if that is your telescope.