Bob's Knobs for Celestron C8 f/10 Secondary with EdgeHD Optics
Collimate your Schmidt Cassegrain Telescope without special tools when you use Bob's Knobs! It's easy: Just grab a Bob's Knob Collimation Thumbscrew and turn it. You can even do it while looking through the eyepiece on many scopes. You'll never drop that pesky little Allen wrench or screwdriver into the grass again. Installation is a snap with the included instructions, and you can undo the modification at any time if you wish. The factory dust cover will fit normally with Bob's Knobs installed on your secondary.
- Installation is a snap with the included instructions
- Modification can be undone at any time
- Knobs are crafted from black plastic, black oxide steel (black) and/or stainless steel (silver)
- No tools required to perform a collimation!
These Bob's Knobs C8edgBO (black oxide steel) collimation knobs will fit the
Celestron 8” (20 cm) f/10 SCT with Fastar secondary and EdgeHD optics.
Knobs: Black oxide steel (black), 12 mm (1/2”) diameter
Threads: Black oxide
- These knobs will fit only the Celestron 8” SCT with Fastar secondary and EdgeHD optics. These telescopes are marked “EDGEHD OPTICS” on the corrector ring. Do not use these knobs on the non-EdgeHD Fastar secondary; the screws on these knobs are too long. Be sure to check that the thread length on our knobs matches the thread length on the factory collimation screws.
- Black oxide steel (shown in photo) is for dry environments. Lightly oil the knobs periodically as an anti-corrosion measure. Stainless steel provides better corrosion protection in coastal or high humidity areas, or in places where dew or other condensation is common. These are the Black oxide steel product.
- The factory dust cover will fit normally with Bob’s Knobs installed.