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Howie Glatter Barlow Laser Collimator Attachment

Howie Glatter Barlow Laser Collimator Attachment

by Howie Glatter
SKU SI-BARATT
$80.00 USD - $80.00 USD
$80.00 USD
$80.00 USD - $80.00 USD
$80.00 USD
Price Match Policy!
  • Enables precise Barlowed primary mirror collimation for Newtonians
  • Integrated design combines a Barlow lens and a white viewing screen in one disc
  • Allows for accurate, solo adjustments at the telescope
  • Fits current model Howie Glatter laser collimators with a 3/8-32 thread
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • Howie Glatter Barlow Laser Collimator Attachment

    The Howie Glatter Barlow Laser Collimator Attachment converts any current Howie Glatter collimator with a 3/8-32 thread into a precise tool for Barlowed primary mirror collimation. This single disc integrates a small Barlow lens and a flat white front screen, enabling accurate, solo adjustment of a Newtonian primary mirror by creating a reference shadow whose position is affected very little by motion of the laser.

    The Principle of Barlowed Collimation: A Stable Primary Mirror Reference

    Barlowed collimation leverages the optical principle of a telescope in reverse. The attachment's small, centered Barlow lens takes the parallel laser beam and diverges it. When this diverging beam reflects off your Newtonian's primary mirror, it becomes a parallel beam again, projecting the shadow of your primary's center mark back up the tube.

    This shadow is displayed on the attachment's white front screen. Because the shadow's position is determined by the primary mirror's tilt and not the laser's alignment in the focuser, it remains stationary even if the laser wobbles. This allows you to adjust the primary mirror's collimation screws to center the shadow around the central hole.

    Integrated Design for Solo Primary Mirror Adjustments

    This attachment replaces the need for a separate Barlow lens and a DIY paper screen. The entire system is contained in a single, threaded disc that attaches directly to the laser collimator, creating a compact and convenient tool for the final, most critical step of Newtonian collimation.

    The attachment allows the user to make solo adjustments of the primary.

    For Current 3/8-32 Thread Howie Glatter Collimators

    This Barlow attachment is designed to fit only the current generation of Howie Glatter laser collimators, which use a 3/8-32 thread on the laser aperture. These collimators are identified by a visible ring.

    It is not compatible with older Glatter collimators with the super fine 5/16-56 thread (no visible ring); the old-thread version of this attachment is discontinued. Please verify your collimator's thread type before purchasing to ensure compatibility.

  • How does the Howie Glatter Barlow Attachment improve primary mirror collimation?

    The attachment diverges the beam so that, after reflection from the primary, it returns as parallel rays carrying the shadow of the primary's center mark to the white screen. The shadow's position is affected very little by motion of the illuminating beam, so it stays put even if the collimator moves in the focuser.

    Can I use the Howie Glatter Barlow Attachment with a laser from another brand?

    No, this attachment is specifically designed to thread onto the aperture of a Howie Glatter laser collimator. It relies on the specific 3/8-32 thread used on current Glatter models and is not a universal fit for other brands.

    How do I know if my Howie Glatter collimator has the correct 3/8-32 thread for this Barlow Attachment?

    Current model Howie Glatter collimators that are compatible with this attachment have a visible ring. Older, incompatible models use a much finer thread (5/16-56) and do not have this ring.

    Is the Howie Glatter Barlow Attachment useful for collimating a Schmidt-Cassegrain telescope?

    No. It is designed for Newtonian primary mirror adjustment. On commercial SCTs only the secondary is user adjustable; the recommended SCT method uses a star test and a single-beam collimator to record the secondary setting.

  • Type Barlow attachment for laser collimators
    Construction Disc with a small mounted Barlow lens and flat white front screen
    Fits Threaded aperture of Howie Glatter collimators, current 3/8-32 thread
    Use Barlowed primary mirror collimation of Newtonians, solo adjustment

    • Barlow laser collimator attachment

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  • Howie Glatter Warranty