4" to 3.5" Adapter with Thumbscrews for 4" Focuser to use QUADTCC (ADA435)

Use the 0.72x QuadTCC or 3.5" Field Flattener with your 4” Focuser!

This adapter will allow owners of Astro-Physics refractors with 4” focusers to use the QuadTCC Telecompressor Corrector!   The adapter fits into the 4” focuser’s drawtube and is secured with the focuser thumbscrews.

The QuadTCC will then insert and be held securely via the three ADA435 thumbscrews.  Fully corrected images with 0.72x compression will be possible using full frame cameras.  

This extension has a net spacing distance of 0.90" (22.9 mm).

Diagram and Instructions

Field Flatteners, TCCs & QUADTCC Imaging Train Options