Optec Inc.
Optec DSI 3.5 Extension Tube Set, 4-piece
Optec DSI 3.5 Extension Tube Set, 4-piece
SKU:SAS50003
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DSI 3.5 x 24 threaded adapters provide a large diameter, robust means of connecting various pieces of imaging equipment to a telescope. This set of 4 extension tubes in 0.5, 0.75, 1 and 1.5 inch lengths allows for the addition of extra length in an imaging train to achieve the correct backfocus distance, a stringent requirement for most astrographs.
Optec P/N: 19889
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Product Details
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Optec-DSI 3.5-inch extension tubes feature female threads on one end with male threads on the opposite end with knurled bases to help attach and detach these tubes. The extensions can be combined and stacked. We believe our four and five piece sets will provide all the needed extension for fixed focal length telescopes with 1/4" (6.35mm) increments using a minimum number of pieces.
All extensions and mounts are made from high strength 6061 aluminum alloy and black anodized. Anti-reflection threading and internal baffles on the largest extension tube help minimize internal reflections. All internal surfaces are painted and baked with a non-reflective surface.
Specifications
1 x 0.5, 1 x 0.75, 1 x 1, and 1 x 1.5 inch lengths.
Compatability
DSI 3.5 x 24 extension tubes are compatible with all other DSI 3.5 x 24 accessories, including the Optec-4300 adapter included with the Optec Gemini.