William Optics Diffraction Spikes Bahtinov Focusing Mask - For Telescope Tube/Dewshield Diameter from 105-148mm (4.2-5.8")

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Latest version with holes and diffration ridges as pictured above. Older version just had diffraction ridges.
William Optics' Diffraction Spikes is an ultra high optical transmission Bahtinov mask which produces the clearest, brightest and longest diffraction spikes facilitating focusing with ease and accuracy.
- Optical transmission: 92% and above (about 3 times brighter than traditional metal masks)
- Made with optical grade PMMA acrylic material
- Easy to mount on many small telescopes that have an outside dewshield diameter of 105mm – 148mm (approx. 4.2" – 5.8")
Other Information
- Country of Manufacture: Taiwan
Latest version with holes and diffration ridges as pictured above. Older version just had diffraction ridges.
William Optics' Diffraction Spikes is an ultra high optical transmission Bahtinov mask which produces the clearest, brightest and longest diffraction spikes facilitating focusing with ease and accuracy.
- Optical transmission: 92% and above (about 3 times brighter than traditional metal masks)
- Made with optical grade PMMA acrylic material
- Easy to mount on many small telescopes that have an outside dewshield diameter of 105mm – 148mm (approx. 4.2" – 5.8")
Latest version with holes and diffration ridges as pictured above. Older version just had diffraction ridges.
William Optics' Diffraction Spikes is an ultra high optical transmission Bahtinov mask which produces the clearest, brightest and longest diffraction spikes facilitating focusing with ease and accuracy.
- Optical transmission: 92% and above (about 3 times brighter than traditional metal masks)
- Made with optical grade PMMA acrylic material
- Easy to mount on many small telescopes that have an outside dewshield diameter of 105mm – 148mm (approx. 4.2" – 5.8")
Other Information
- Country of Manufacture: Taiwan
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William Optics Diffraction Spikes Bahtinov Focusing Mask - For Telescope Tube/Dewshield Diameter from 105-148mm (4.2-5.8")


















