Cloud Break Optics

Threaded 2.7" Extension with Internal T-thread (A3511)

Threaded 2.7" Extension with Internal T-thread (A3511) - Main image
$40.2 $60 In stock

Category: Focusing

Description

Realize the full potential of your Fluorite Flatfield Converter (BPFFC) or 2" Convertible Photo-Visual Barlow (BARCON) when imaging by using this extension. The internal T-thread on this extension allows you to attach your BPFFC, BARCON or other accessory with male T-threads INSIDE the 2.7" extension tube. In this way, the camera, filter wheel, off-axis guider, and/or other accessories are all supported by the much more robust and rigid 2.7" tube system, and the Barlow only needs to support its own weight inside the extension tube. This is particularly important when imaging at some of the higher magnification factors achievable with the BPFFC where over a foot of extension may be used between the Barlow optic and the focal plane. The maximum OD of the T-thread accessory is 2.5". Please see this A3511 System Chart for component options.

This 2.7" extension has a net spacing distance of 0.75" (19.05 mm).

It has a net spacing distance of 0.9" (22.86 mm) for the internal optic.

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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (4.8 / 5 · 5 reviews)

Benjamin ★★★★★

Finally got my imaging train sorted out — this 2.7" extension locks onto the internal T-thread perfectly, and the added length clears my camera without any vignetting. Solid machining, threads engage smoothly every time.

Aurora K. ★★★★★

This extension has a really clean internal T-thread that mates perfectly with my camera adapter, no wobble at all. I was able to dial in the exact back focus distance I needed for my setup, and the threads are smooth without any binding.

George Q. ★★★★★

Finally got the spacing dialed in for my imaging train. The internal T-thread makes connecting my camera straightforward, no adapters needed.