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IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
Daystar Quantum Extension Tube - 2" 80mm Long

Daystar Quantum Extension Tube - 2" 80mm Long

by Daystar Filters
SKU DAY-GM2D2
$79.00 - $79.00
$79.00
$79.00 - $79.00
$79.00
Price Match Policy!
  • Adds 80mm of physical length to a 2" focuser
  • Provides 85mm of additional outward focus travel
  • Standard 2" male and female barrels
  • Features a non-marring brass compression ring
  • Black and red anodized finish
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  • Description
  • FAQ
  • Specifications
  • In the Box
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  • Warranty

  • Daystar Quantum Extension Tube - 2" 80mm Long

    The Daystar Quantum Extension Tube solves common back-focus problems by adding 80mm of physical length to your 2" focuser drawtube, creating 85mm of additional outward focus travel. This male-to-female extension is essential for achieving a sharp image with specific camera and eyepiece combinations that require more back focus than your telescope natively provides.

    80mm Extension for Gaining 85mm of Focus Travel

    Certain optical configurations, especially those involving focal reducers, off-axis guiders, or specific eyepieces like binoviewers, often shift the focal plane outwards. If your focuser runs out of travel before the image snaps into focus, this 80mm extension tube provides the necessary extra length to bridge that gap, ensuring you can properly frame and focus your target.

    Secure, Non-Marring 2" Barrel Design

    Daystar has engineered this extension tube for both security and equipment safety. The barrel features a brass compression ring that grips your eyepiece or camera nosepiece firmly without the risk of scratching or scoring the barrel, which is a common problem with simple set screws. A stainless steel set screw provides the locking force, while the black and red anodized finish ensures durability and reduces internal reflections.

  • When would I need the Daystar Quantum 80mm Extension Tube for my SCT?

    A Schmidt-Cassegrain Telescope (SCT) often requires an extension tube when using accessories that consume significant back focus, such as a focal reducer paired with an off-axis guider and filter wheel. The Daystar Quantum 80mm Extension Tube provides the necessary spacing to bring your imaging train to focus.

    Will the Daystar Quantum 80mm Extension Tube cause vignetting with my full-frame camera?

    The 2" diameter is designed to pass the light cone from most amateur telescopes without causing significant vignetting on its own. However, the further a sensor is from the focal point, the more susceptible the system is to vignetting from the telescope's own optics. While this tube is compatible with full-frame cameras, taking flat frames is always recommended to correct for any field illumination issues.

    What is the difference between the 80mm length and 85mm focus extension?

    The physical body of the Daystar Quantum Extension Tube is 80mm long. However, due to the way it seats in the focuser and holds the eyepiece, it effectively pushes the focal plane outwards by 85mm. This is the critical number for calculating your back focus needs.

    What is the purpose of the brass insert in the Daystar Quantum Extension Tube?

    The brass insert is a compression ring. When you tighten the stainless steel set screw, it presses the soft brass ring evenly against your eyepiece or camera barrel. This provides a secure, centered grip without leaving the gouges or scratches that a bare steel screw tip would cause on your equipment.

    Is the Daystar Quantum 80mm Extension Tube threaded for filters?

    The manufacturer's specifications do not indicate that this extension tube is threaded for 2" filters. It is designed purely to extend the focuser's light path and provide a secure connection point for other 2" accessories.

    How does the Daystar Quantum Extension Tube attach to my telescope?

    The extension tube has a 2" male barrel that slides directly into your telescope's 2" focuser or visual back, just like an eyepiece. You then insert your 2" diagonal, camera nosepiece, or other accessory into the 2" female end of the extension tube and lock it in place with the set screw.

  • Length 80mm
    Focus Extension Provided 85mm
    Diameter 2"
    Connection Type Male to Female 2" Drawtube
    Locking Mechanism Stainless Steel Set Screw with Brass Compression Ring
    Finish Black/Red Anodized

    • Daystar Quantum 2" Extension Tube (80mm)

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  • Daystar Filters Warranty