3D Astro Bahtinov Focus Mask - 58.5mm ID for FMA180 PRO
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Bahtinov mask to aid in focusing your FMA180-PRO. Will fit other guidescopes that have a dewshield outside diameter of 58.5mm.
We're not sure how necessary or effective this might be on a small-aperture guidescope, but several people have expressed interest in this item, so here it is.
With the mask on, you can see a diffraction spike pattern. Focus until you achieve a symetrical pattern. Once the best focus has been achieved, you can remove the mask and use the guide scope as normal.
This mask is deliberately designed to fit loosely over the guidescope dewshield so that it can be removed very easily when focusing is accomplished. It does not have a firm fit like an end cap would so that the imaging setup isn’t disturbed when you take this off.
3D printed from PLA.
Color of current stock is silver-gray but is subject to change without notice.
Other Information
- Country of Manufacture: United States
Bahtinov mask to aid in focusing your FMA180-PRO. Will fit other guidescopes that have a dewshield outside diameter of 58.5mm.
We're not sure how necessary or effective this might be on a small-aperture guidescope, but several people have expressed interest in this item, so here it is.
With the mask on, you can see a diffraction spike pattern. Focus until you achieve a symetrical pattern. Once the best focus has been achieved, you can remove the mask and use the guide scope as normal.
This mask is deliberately designed to fit loosely over the guidescope dewshield so that it can be removed very easily when focusing is accomplished. It does not have a firm fit like an end cap would so that the imaging setup isn’t disturbed when you take this off.
3D printed from PLA.
Color of current stock is silver-gray but is subject to change without notice.
Bahtinov mask to aid in focusing your FMA180-PRO. Will fit other guidescopes that have a dewshield outside diameter of 58.5mm.
We're not sure how necessary or effective this might be on a small-aperture guidescope, but several people have expressed interest in this item, so here it is.
With the mask on, you can see a diffraction spike pattern. Focus until you achieve a symetrical pattern. Once the best focus has been achieved, you can remove the mask and use the guide scope as normal.
This mask is deliberately designed to fit loosely over the guidescope dewshield so that it can be removed very easily when focusing is accomplished. It does not have a firm fit like an end cap would so that the imaging setup isn’t disturbed when you take this off.
3D printed from PLA.
Color of current stock is silver-gray but is subject to change without notice.
Other Information
- Country of Manufacture: United States
3D Astro Bahtinov Focus Mask - 58.5mm ID for FMA180 PRO