GSO 25mm Extension Tube for 4.5", 6" & 8" RC / CC Telescopes with M90x1 Thread
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- GSO 25mm-long x 90mm extension ring for select GSO-made RC/CC telescopes
- Ideal for adjusting back focus to minimize extension of focuser tube
- Made of black-anodized aluminum with anti-reflection threading
GSO 25mm Extension Tube for 4.5", 6" and 8" RC or CC Telescopes with M90x1 Thread # FF083.
This adapter features M90x1 male threads on one side and M90x1 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) or Classical Cassegrain (CC) telescopes if you need to adjust back-focus for your imaging setup.
Some GSO RC and CC 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 or if your telescope does not come with one. 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 = 34mm (1.34")
- Length of M90 male thread (including unthreaded undercut) = 8.6mm (0.34")
- Length of M90 female thread (including unthreaded undercut) =10mm (0.40")
- Extension provide = 25mm (0.98")
- Outside diameter = 94mm (3.70")
- Inside diameter (clear aperture) = 78mm (3.08")
- Weight = 4.5oz (128g)
Other Information
- Country of Manufacture: Taiwan
GSO 25mm Extension Tube for 4.5", 6" and 8" RC or CC Telescopes with M90x1 Thread # FF083.
This adapter features M90x1 male threads on one side and M90x1 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) or Classical Cassegrain (CC) telescopes if you need to adjust back-focus for your imaging setup.
Some GSO RC and CC 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 or if your telescope does not come with one. 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 = 34mm (1.34")
- Length of M90 male thread (including unthreaded undercut) = 8.6mm (0.34")
- Length of M90 female thread (including unthreaded undercut) =10mm (0.40")
- Extension provide = 25mm (0.98")
- Outside diameter = 94mm (3.70")
- Inside diameter (clear aperture) = 78mm (3.08")
- Weight = 4.5oz (128g)
- GSO 25mm-long x 90mm extension ring for select GSO-made RC/CC telescopes
- Ideal for adjusting back focus to minimize extension of focuser tube
- Made of black-anodized aluminum with anti-reflection threading
GSO 25mm Extension Tube for 4.5", 6" and 8" RC or CC Telescopes with M90x1 Thread # FF083.
This adapter features M90x1 male threads on one side and M90x1 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) or Classical Cassegrain (CC) telescopes if you need to adjust back-focus for your imaging setup.
Some GSO RC and CC 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 or if your telescope does not come with one. 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 = 34mm (1.34")
- Length of M90 male thread (including unthreaded undercut) = 8.6mm (0.34")
- Length of M90 female thread (including unthreaded undercut) =10mm (0.40")
- Extension provide = 25mm (0.98")
- Outside diameter = 94mm (3.70")
- Inside diameter (clear aperture) = 78mm (3.08")
- Weight = 4.5oz (128g)
Other Information
- Country of Manufacture: Taiwan
GSO 25mm Extension Tube for 4.5", 6" & 8" RC / CC Telescopes with M90x1 Thread