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Baader T-2 Locking Ring (2mm length)

Baader T-2 Locking Ring (2mm length)

by Baader Planetarium
SKU BAA-2958120
$31.00 - $31.00
$31.00
$31.00 - $31.00
$31.00
Price Match Policy!
  • Adds a precise 2mm of optical path length
  • Enables full 360° rotational adjustment for cameras and accessories
  • Locks components securely at any orientation
  • Standard T-2 (M42x0.75) internal threads on both sides
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Downloads
  • Warranty

  • Baader T-2 Locking Ring (2mm length)

    The Baader T-2 Locking Ring is a fundamental component for astrophotography, solving the critical problem of component orientation by adding a precise 2mm of optical path length to any T-2 thread system. This ultra-thin ring allows for fine-tuning back focus and, most importantly, locking the rotational angle of your camera or filter wheel—a function that a standard, fixed 2mm spacer cannot perform.

    Achieve Perfect Camera Angle and Spacing with 2mm of Adjustment

    When you connect T-threaded components, they tighten at an arbitrary angle, leaving your camera misaligned with the sky. The Baader T-2 Locking Ring allows you to back the camera off to the perfect orientation and then tighten the ring against it, locking it securely in place. This ensures your framing is always exactly as you intend.

    Beyond orientation, the ring serves as a precision 2mm spacer. When your back focus is off by a small, known amount, this ring provides the exact increment needed to achieve the perfect distance required by your field flattener or coma corrector for sharp stars across the entire frame. While providing this control, note that a locking ring occupies several threads to function; ensure you have enough remaining thread engagement for heavy cameras.

    • Complete Rotational Freedom: Loosen the ring, rotate your camera to the desired angle for framing galaxies like M31 or nebulae like the Horsehead (Barnard 33), and lock it down without changing focus.
    • Precision Back-Focus Tuning: Use it as a calibrated 2mm spacer when you need just a small extension to hit the critical 55mm back focus distance common to many correctors.
    • Low-Profile Design: At only 2mm thick, it adds minimal length to your imaging train, preserving precious back focus for other accessories.

  • What is the main purpose of the Baader T-2 Locking Ring (2mm)?

    Its primary purpose is to allow you to set the rotational angle of a T-threaded accessory, like a camera or filter wheel. You thread the accessory on, back it off to the correct orientation, and then tighten the locking ring against it to secure it in that position. It also doubles as a precision 2mm spacer.

    How does this 2mm Baader T-2 Locking Ring differ from a standard 2mm T-2 extension tube?

    Both add 2mm of optical path length. However, a standard extension tube has fixed threads and does not allow for rotational adjustment. The Baader T-2 Locking Ring is specifically designed to lock another component at any angle within the 360° rotation of the threads, a capability the fixed tube lacks.

    If I need to correct the spacing for my MPCC III on a Newtonian, can this 2mm ring help?

    Yes, absolutely. The Baader MPCC III requires a precise 55mm back focus. If your current setup results in a spacing of 53mm, adding this 2mm locking ring will provide the exact distance needed to achieve sharp, coma-free stars to the edge of the field. It's an ideal tool for such fine adjustments.

    Will the Baader T-2 Locking Ring (2mm) work with accessories from other brands like ZWO or QHY?

    Yes. The T-2 thread (M42x0.75) is a universal standard in astrophotography. This locking ring will work with any T-threaded camera, filter wheel, off-axis guider, or accessory from any manufacturer that adheres to the T-2 standard.

    How do I use the Baader 2mm Locking Ring to adjust my camera's orientation?

    First, thread the locking ring all the way onto the male T-thread of your telescope or adapter. Then, thread your camera on until it makes contact with the ring. Finally, while holding the camera at your desired angle, unthread the locking ring until it presses firmly against the camera body, locking it in place.

    My camera is just slightly out of focus with my flattener; could the 2mm T-2 Locking Ring be the solution?

    It could be. If you have determined that your sensor is 2mm too close to the flattener, adding this ring will provide the correct spacing. It's a precise and simple way to fix minor back focus errors without having to buy a whole new set of extension tubes.

  • Optical Length 2mm
    Thread Type T-2 (M42x0.75)
    Inner Diameter / Clear Aperture (mm) 41
    Outer Diameter 49
    Type of Adapter Same-Thread Adapter, Variable Focusing
    T-2 Part # 35
    Usage for rotation clamping
    Adaptable to heavy CCD cameras
    Telescope-side connection M42x0.75 (T2) Female
    Camera-side connection M42x0.75 (T2) Female

    • Baader T-2 Locking Ring (2mm length)

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  • Baader Planetarium Warranty Policy