Tuesday, February 8, 2011

4se Celestron with Barlow t-Adapter and Canon EOS 40D

This post shows the second assembled configuration for attaching a Canon EOS DSLR to the Celestron NexStar 4SE. In this setup, the camera is mounted using the 1¼-inch Barlow T-Adapter (93640), providing additional magnification while still operating in true prime-focus mode.

This configuration follows the first assembled setup using the T-Adapter-C90 on the rear port. While both deliver native prime focus, the camera is attached to a different optical output port of the telescope.

Celestron 4SE with 1.25-inch Barlow T-Adapter, Canon EOS T-ring and Canon EOS 40D attached to the top diagonal port using the flip mirror system for prime focus astrophotography

Second assembled configuration: 4SE with Barlow T-Adapter 1¼", Canon EOS T-ring, and Canon EOS 40D on the top optical port

How This Assembly Differs from the First Assembled Configuration

In the first assembled setup (Part 2), the camera attaches to the rear threaded photographic adapter. In this second configuration, the camera attaches to the top diagonal barrel, the same position normally used by the finderscope bracket.

Rear port (Part 2): Camera inline with optical tube.
Top port (this post): Camera faces upward for easier LCD viewing and better weight balance.

Both positions are true prime focus, only using different light output paths.

Understanding the Two Camera Attachment Points on the Celestron 4SE

The Celestron NexStar 4SE includes a built-in Flip Mirror Control that allows light to exit through either:

Rear threaded photographic port (used in Part 2)
Top diagonal port (used in this Part 3 configuration)

Switching the flip mirror determines which port receives the light. This second assembled configuration simply uses the top port + 1¼-inch Barlow T-Adapter for increased magnification and easier access to the camera screen.