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Optec DSI Direct Screw Interface Adapters

Optec DSI Direct Screw Interface adapters use a large 3.5" threaded connection to join Optec focusers and rotators to telescopes and cameras without set screws or compression rings. The line includes a 3.5"x24tpi to M72x1 adapter for Takahashi telescopes, an OPTEC-4300 to DSI 3.5" adapter and a five-piece 3.5" extension tube set.

A fully threaded train keeps heavy cameras rigid and square to the optical axis, which helps against tilt and flexure in long exposures.

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$250.00 - $250.00
$250.00
$250.00 - $250.00
$250.00

Optec DSI 3.5" Extension Tube Set - 5 Pieces

OPC-19890

Rich Simons of Deep Sky Instruments and Optec have jointly developed a new, larger diameter standard spacer for large aperture telescopes. Like th...

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$250.00 - $250.00
$250.00
$250.00 - $250.00
$250.00
$95.00 - $95.00
$95.00
$95.00 - $95.00
$95.00

Optec DSI 3.5"x24tpi(M) to M72x1(M) Takahashi Adapter

OPC-19917

Optec-DSI 3.5x24tpi male thread to M72x1mm (male) Takahashi thread. Outside Diameter: 3.82" (97.0mm) Overall Height: 0.74" (18.8mm) Clear Aperture...

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$95.00 - $95.00
$95.00
$95.00 - $95.00
$95.00
$135.00 - $135.00
$135.00
$135.00 - $135.00
$135.00

Optec OPTEC-4300 to DSI 3.5"(F) Adapter

OPC-19830

The #19830 OPTEC-4300 to female Optec/DSI 3.5" threaded receiver allows any combination of our DSI 3.5-inch spacers to be easily installed on the c...

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$135.00 - $135.00
$135.00
$135.00 - $135.00
$135.00