Improved Sensitivity Tri-Bahtinov Mask

Improved Sensitivity Tri-Bahtinov Mask

SKU: 3bah01

Focusing and Collimation Tool


The Skylabs Improved Sensitivity Tri-Bahtinov masks are designed to obtain a very accurate focus and very precise collimation of reflector telescopes, including Schmidt-Cassegrain, Maksutov-Cassegrain, Classical Cassegrain, Ritchey-Chretien, Maksutov-Newtonian, and Newtonian Telescopes.


The Tri-Bahtinov mask improved by C.Y. Tan and Satoru Takagi has incorporated several enhancements compared to the traditional Bahtinov mask. It allows evaluating an even more accurate focus, and it also allows detecting and correcting a misscollimation of a reflector telescope.


This affordable tool is the result of vibrant cooperation and open-source contributions inside the astrophotography community.

  • Product Information

    While the traditional Bahtinov masks deliver a diffraction pattern, creating a set of three fine spike lines around a bright star, the Tri-Bahtinov masks generate a set of 18 spikes, which is crucial to assess an accurate focus in astrophotography.

    The Skylabs Improved Sensitivity Tri-Bahtinov mask is based on eco-friendly high density cardboard (kraftboard). The material is not only durable but also delicate with the telescope optics, especially for MCT, MNT, and SCT. The thin material and the CNC precision cut shape ensures an extraordinary precise diffraction pattern.

  • How to Order

    Each Skylabs Improved Sensitivity Tri-Bahtinov is created on-demand as it depends on each telescope's characteristics. To request one of these masks, you will need to provide the following accurate values in millimeters

    • Telescope brand and model.
    • Focal Length.
    • Secondary Holder Diameter: is the diameter of the secondary holder.
    • Secondary Diameter: is the diameter of the secondary mirror.
    • Aperture Diameter: is the diameter of the main mirror.
    • Inner Tube Diameter: is the diameter of the inside wall of the telescope tube.
  • Size Compatibility

    We recommend this type of mask for telescopes over 140mm of aperture. If you have a smaller telescope, consider using the Skylabs Enhanced Bahtinov masks, which has been designed for camera lenses and small telescopes, and it is several times brighter than traditional ones.

    Currently, Skylabs can not provide Tri-Bahtinov masks for telescopes with an outer diameter bigger than 300mm.

  • Each order includes

    • Tri-Bahtinov Mask
    • Tri-Bahtinov Mask Cover (for collimation)
    • Quick Guide

    Telescope, camera or other elements shown in the pictures are not included.

  • Shipping Information

    Orders typically ship out within 2 business days, but custom orders occasionally take longer. New Zealand orders are usually delivered within 2 business days, Australia within 4 to 6 business days, and the rest of the world within 6 to 10 business days.


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