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Baader Variable Locking Extension - 12-16mm
Baader Variable Locking Extension - 12-16mm

Baader Variable Locking Extension - 12-16mm

by Baader Planetarium
SKU BAA-2958130
CA$66.00 - CA$66.00
CA$66.00
CA$66.00 - CA$66.00
CA$66.00
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  • Provides a variable extension range of 12mm to 16mm
  • Features a locking ring to prevent unwanted rotation
  • Standard T-2 (M42x0.75) threads for universal compatibility
  • An essential component for achieving precise back focus
  • Combines three Baader T-2 parts: #26, #34, and #35
1 in stock
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  • Description
  • FAQ
  • Specifications
  • In the Box
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  • Warranty

  • Baader Variable Locking Extension - 12-16mm

    Achieving precise back focus is non-negotiable for sharp, coma-free images, and the Baader Variable Locking Extension delivers a critical 12mm to 16mm of adjustable length within the standard T-2 thread system. This pre-assembled unit is a combination of the T-2 Inverter Ring (#26), Conversion Ring (#34), and Lockring (#35), engineered to eliminate spacing errors and prevent unwanted component rotation in your imaging train.

    Precision Back Focus: Dialing in 12mm to 16mm of T-2 Spacing

    While fixed T-2 extension rings can get you close to the ideal 55mm back focus required by most coma correctors and field flatteners, "close" isn't good enough. This variable extension bridges the gap, offering a 4mm range of fine adjustment. It allows you to precisely dial in the exact distance between your corrector and sensor plane, compensating for filter thickness and thread variations to achieve pinpoint stars across the entire frame.

    The T-2 System: Locking Rotation and Combining Components

    Beyond simple spacing, this component's locking ring is crucial for maintaining a rigid imaging train. Once you achieve the desired extension, a simple twist of the knurled lockring secures the position, preventing your camera or filter wheel from rotating and ruining your framing. As a core part of the Baader T-2 Astro System, this extension serves as a versatile problem-solver, allowing you to build robust, custom optical configurations without flexure or instability.

  • What is the primary use for the Baader Variable Locking Extension?

    Its main purpose is to fine-tune the back focus distance in an imaging train. It's used to precisely set the space between a field flattener, reducer, or coma corrector and the camera sensor, which is essential for achieving a sharp, flat field of view. The 12mm to 16mm adjustable range is ideal for closing moderate gaps in the optical path.

    My imaging train is about 14mm short of the required back focus. Is the Baader Variable Locking Extension the right solution?

    Yes, absolutely. The 12mm to 16mm range of this extension is perfectly suited for this scenario. You can set it to the required 14mm and use the locking ring to secure it, ensuring your sensor is at the optimal distance from your corrective optics.

    How does the locking mechanism on the Baader Variable Extension work?

    The extension consists of two threaded parts and a separate lockring. You first unscrew the main barrels to achieve your desired extension length. Then, you tighten the independent T-2 lockring (#35) against the body of the extension. This creates counter-pressure that locks the threads in place, preventing any further rotation or slippage.

    Can I use the Baader 12-16mm extension to set the orientation of my off-axis guider?

    Yes, this is an excellent application for it. The locking feature allows you to set the required spacing and then rotate the entire assembly to position your off-axis guider's prism correctly relative to the main camera sensor. Once you have the perfect orientation, you can tighten the lockring to secure the OAG's position for the imaging session.

    Is this Baader extension compatible with non-Baader T-2 accessories?

    Yes. The T-2 thread is an industry standard (M42x0.75). This variable extension will connect to any standard T-threaded component from any manufacturer, including T-rings for DSLRs, camera noses, filter wheels, and off-axis guiders.

    What individual Baader parts make up the 12-16mm Variable Locking Extension?

    This is a pre-assembled unit combining three specific components from the Baader T-2 Astro System:

    • T-2 Inverter Ring (#26)
    • T-2 Conversion Ring (#34)
    • T-2 Lockring (#35)
  • Extension Range 12mm - 16mm
    Thread Type T-2 (M42x0.75)
    Function Variable Locking Extension Ring
    Component Parts Baader T-2 Parts #26, #34, #35
    Net weight (kg) 0.02
    Inner Diameter / Clear Aperture (mm) 39
    Outer Diameter 49
    Type of Adapter Extension, Variable Focusing
    Optical length (mm) 12 (10) – 16

    • Baader Variable Locking Extension - 12-16mm

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  • Baader Planetarium Warranty