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Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)
Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)
Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)
Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)
Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)
Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)
Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)
Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)
Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)
Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)
Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)
Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)
Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)
Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)
Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)

Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)

by Baader Planetarium
SKU BAA-2958500B
$76.00 - $76.00
$76.00
$76.00 - $76.00
$76.00
Price Match Policy!
  • Adds only 7mm of optical length to your imaging train
  • Connects 2" female SCT threads to male T-2 (M42x0.75) threads
  • Ultra-short design preserves critical back-focus space
  • Ideal for use with focal reducers and off-axis guiders
  • Precision machined for a rigid, flex-free connection
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  • Description
  • FAQ
  • Specifications
  • In the Box
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  • Warranty

  • Baader Ultra Short T-Adapter - 2" SCT(F) Thread/T-2(M)

    The Baader Ultra Short T-Adapter is a critical component for Schmidt-Cassegrain telescope (SCT) imagers, connecting a standard female 2-inch SCT thread to a male T-2 thread while consuming a minimal 7mm of optical length. This ultra-compact design is engineered specifically to solve back-focus problems, enabling the use of complex imaging trains with accessories like focal reducers, filter wheels, and off-axis guiders where every millimeter is crucial.

    The 7mm Solution for Critical SCT Back-Focus

    SCTs, especially when used with f/6.3 or f/7 focal reducers, have a strictly defined back-focus distance that must be maintained for optimal correction. The Baader Ultra Short T-Adapter addresses this by providing the most compact connection possible between the telescope's rear cell and your T-threaded accessories. Its 7mm optical path leaves maximum room for essential equipment, preventing situations where you cannot reach focus with a full imaging setup.

    Baader's 7mm Adapter vs. Standard T-Adapters: Reclaiming Optical Path

    Standard SCT T-adapters can often consume 25mm or more of back-focus, which is often too much for a complete OAG and filter wheel configuration. By replacing a bulky adapter with this 7mm Baader component, you reclaim precious optical path. This can be the single deciding factor that allows you to add an off-axis guider to your train or achieve the correct sensor spacing for a field flattener, ensuring sharp stars across the entire frame.

  • Why is the Baader Ultra Short T-Adapter's 7mm length so important for an SCT with an f/6.3 reducer?

    An f/6.3 focal reducer has a specific back-focus requirement (typically around 105mm) for proper optical correction. The Baader Ultra Short T-Adapter's minimal 7mm optical length maximizes the available space within that budget for your camera, filter wheel, and off-axis guider, which a longer, standard adapter might prevent.

    Can I use the Baader Ultra Short T-Adapter to attach my ZWO ASI camera to a Celestron 8" SCT?

    Yes. This adapter is perfect for that application. The 2" female SCT thread screws directly onto the rear cell of the Celestron 8" SCT, and the male T-2 thread connects to the T-ring or main body of most ZWO ASI cameras and their included T-2 spacers.

    What problem does the Baader Ultra Short T-Adapter solve?

    It solves the problem of running out of back-focus. Many SCT imagers find they cannot reach focus after adding accessories like an off-axis guider because their standard adapter is too long. This ultra-short adapter reclaims that lost space, often making a previously impossible imaging configuration viable.

    What are the exact threads on the Baader Ultra Short T-Adapter?

    The adapter features a female 2" SCT thread (2"-24 TPI) on the telescope side and a male T-2 thread (M42x0.75) on the camera/accessory side. This is a standard combination for most SCTs and astronomy cameras.

    Will this Baader adapter introduce flexure into my imaging train?

    No. The Baader Ultra Short T-Adapter is machined from high-grade aluminum to precise tolerances. Its single-piece construction and secure threading provide a rigid, flex-free connection, which is essential for maintaining alignment and producing sharp images.

    Is the Baader Ultra Short T-Adapter compatible with other Baader T-2 system components?

    Absolutely. This adapter is a core part of the Baader Astro T-2 System. It allows you to seamlessly integrate your SCT with the extensive range of Baader T-2 extension tubes, changers, and other accessories to build a fully threaded, modular imaging setup.

  • Optical Length 7mm
    Telescope Side Connection 2" SCT Female Thread (2"-24 TPI)
    Accessory Side Connection T-2 Male Thread (M42x0.75)
    Net weight (kg) 0.03
    Inner Diameter / Clear Aperture (mm) 39
    Outer Diameter 56
    Type of Adapter Reducing Adapter
    Inner Connection (lens sided) 2"/SCT Thread (50.8mm)
  • Baader Planetarium Warranty