GSO 25mm Extension Tube for 10" and 12" RC Telescopes with M117x1 Thread
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GSO 25mm Extension Tube for 10" and 12" RC Telescopes with M117x1 Thread # FF178.
This adapter features M117x1 male threads on one side and M117x1 female threads on the other side, and provides 25mm of additional spacing. You can use this to move the focuser farther away from the rear cell of select GSO Ritchey-Chretien (RC) telescopes if you need to adjust back-focus for your imaging setup.
Most GSO RC telescopes already come with some extension rings (see individual telescope descriptions for details of included accessories), but you can use this spacer ring if you need additional spacing for your specific setup. It is also preferable to use a spacer like this instead of racking the telescope focuser out in order to minimize flexing, especially if you use heavy cameras or imaging accessories.
Precision machined from black anodized aluminum. Painted flat black and features anti-reflection grooves on the inside. Made in Taiwan.
Specifications:
- Total length = 33.8mm (1.33")
- Length of M117 male thread (including unthreaded undercut) = 8.6mm (0.34")
- Length of M117 female thread (including unthreaded undercut) =10mm (0.40")
- Extension provide = 25mm (0.98")
- Outside diameter = 120.9mm (4.76")
- Weight = 6.7oz (188g)
Other Information
- Country of Manufacture: Taiwan
GSO 25mm Extension Tube for 10" and 12" RC Telescopes with M117x1 Thread # FF178.
This adapter features M117x1 male threads on one side and M117x1 female threads on the other side, and provides 25mm of additional spacing. You can use this to move the focuser farther away from the rear cell of select GSO Ritchey-Chretien (RC) telescopes if you need to adjust back-focus for your imaging setup.
Most GSO RC telescopes already come with some extension rings (see individual telescope descriptions for details of included accessories), but you can use this spacer ring if you need additional spacing for your specific setup. It is also preferable to use a spacer like this instead of racking the telescope focuser out in order to minimize flexing, especially if you use heavy cameras or imaging accessories.
Precision machined from black anodized aluminum. Painted flat black and features anti-reflection grooves on the inside. Made in Taiwan.
Specifications:
- Total length = 33.8mm (1.33")
- Length of M117 male thread (including unthreaded undercut) = 8.6mm (0.34")
- Length of M117 female thread (including unthreaded undercut) =10mm (0.40")
- Extension provide = 25mm (0.98")
- Outside diameter = 120.9mm (4.76")
- Weight = 6.7oz (188g)
GSO 25mm Extension Tube for 10" and 12" RC Telescopes with M117x1 Thread # FF178.
This adapter features M117x1 male threads on one side and M117x1 female threads on the other side, and provides 25mm of additional spacing. You can use this to move the focuser farther away from the rear cell of select GSO Ritchey-Chretien (RC) telescopes if you need to adjust back-focus for your imaging setup.
Most GSO RC telescopes already come with some extension rings (see individual telescope descriptions for details of included accessories), but you can use this spacer ring if you need additional spacing for your specific setup. It is also preferable to use a spacer like this instead of racking the telescope focuser out in order to minimize flexing, especially if you use heavy cameras or imaging accessories.
Precision machined from black anodized aluminum. Painted flat black and features anti-reflection grooves on the inside. Made in Taiwan.
Specifications:
- Total length = 33.8mm (1.33")
- Length of M117 male thread (including unthreaded undercut) = 8.6mm (0.34")
- Length of M117 female thread (including unthreaded undercut) =10mm (0.40")
- Extension provide = 25mm (0.98")
- Outside diameter = 120.9mm (4.76")
- Weight = 6.7oz (188g)
Other Information
- Country of Manufacture: Taiwan
GSO 25mm Extension Tube for 10" and 12" RC Telescopes with M117x1 Thread