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Baader Double T-Filterholder - 1.25"

Baader Double T-Filterholder - 1.25"

by Baader Planetarium
SKU BAA-1508030
$58.00 - $58.00
$58.00
$58.00 - $58.00
$58.00
Price Match Policy!
  • Holds a 1.25" filter inside the adapter
  • Filter threads in from either side
  • T-2 (M42x0.75) threads on both sides
  • Zero optical length
  • Made for adding 1.25" filters in front of Baader binoviewers
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Downloads
  • Warranty

  • Baader Double T-Filterholder - 1.25"

    The Baader Double T-Filterholder is a short ring with T-2 (M42x0.75) threads on both sides and an internal 1¼" (M28.5) filter thread. A 1.25" filter can be threaded in from either side and sits within the adapter, so you can place a filter in a T-2 train, for example in front of a Baader binoviewer, without adding optical length.

    A 1.25" Filter Inside Your T-2 Train

    The holder carries an internal M28.5 thread, the standard 1.25" filter thread. A filter can be threaded in from either side and then sits within the adapter.

    Baader uses it to attach 1.25" filters in front of its binoviewers, where a single filter covers the light going to both eyepieces.

    T-2 System Integration for a Secure, Low-Profile Connection

    Designed as part of the Baader T-2 Astro System, the Double T-Filterholder features standard T-2 (M42x0.75) male threads on both sides. This ensures direct, secure integration into virtually any established imaging train, connecting between a camera nosepiece, off-axis guider, or focal reducer without flexure.

    Its optical length is 0 mm, which suits optical systems with tight spacing requirements, such as those using coma correctors or reducers.

  • What threads does the Baader Double T-Filterholder use for connection?

    The holder uses the standard T-2 thread system, which is M42x0.75. It has male T-2 threads on both the telescope side and the camera side, allowing it to be inserted directly into common imaging trains.

    Will this 1.25" filter holder cause vignetting with my camera?

    With cameras that have small to medium sensors (up to approximately APS-C size, depending on the telescope's focal ratio), vignetting is typically not an issue. However, with full-frame (24x36mm) sensors, a 1.25" filter will almost always cause significant vignetting. For full-frame sensors, a 2-inch filter solution is recommended.

    Can I use 2" filters with the Baader Double T-Filterholder?

    No, this model is designed exclusively for standard 1.25" (M28.5 thread) filters. Baader Planetarium offers different solutions for 2" filters.

  • Net weight (kg) 0.01
    Compatible Brands Astro T-2, Baader Planetarium, Celestron
    Inner Diameter / Clear Aperture (mm) 28
    Outer Diameter 46
    Type of Adapter Filter holder, Same-Thread Adapter
    T-2 Part # 31
    Inner Connection (eyepiece/-camera-sided) M28.5
    Outer Connection (eyepiece/-camera-sided) M42 x 0.75 (T-2)
    Inner Connection (lens sided) M28.5
    Outer Connection (lens sided) M42 x 0.75 (T-2)
    Adaptable to SBIG CCD-Cameras, CFW-8 color filter wheel
    Adapters Family T-2 System
    Telescope-side connection M42x0.75 Male (T-2)
    Camera-side connection M42x0.75 Male (T-2)
    Optical length 0 mm

    • Baader Double T-Filterholder - 1.25"

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  • Baader Planetarium Warranty