Takahashi SD Tube for FS60C Flattener (TKA20583)

Description

Takahashi SD Tube for FS60C Flattener (TKA20583)

This SD (short-distance) extension tube is engineered to fine-tune the back-focus when using the dedicated FS60C flattener. With approximately 6mm of added optical length, the TKA20583 allows true prime-focus sharpness from close-in terrestrial imaging to the night sky, maintaining exact parfocality across the full field.

Machined from black-anodized aluminum with precise internal threading, it aligns the flattener and camera train without inducing tilt or misalignment. Its the essential missing link when pairing the FS60C flattener to a DSLR or modern color CMOS camera on the compact FS60C or FS60CB refractor.

CloudyNights Community Insight

Among users discussing the FS60 series imaging train, many emphasize the importance of the SD tubes exact length. One observer noted that it is essential for getting the flattener to focus to infinity and ensures flat stars across the corner, even on APSC sensors. This consensus underscores its role in achieving crisp, well-corrected wide-field images.

Observing Tip

Install the SD tube between the flattener and camera adapterideally before adding the camerato ensure that all components align snugly without having to adjust focuser drawtube each time. Its a small part that saves big headaches: consistent focus, best corner stars, and avoidance of flange lock-ups during intense imaging sessions.