Bob's Knobs for Celestron C8 f/10 EdgeHD 8" Secondary
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Collimate your Catadioptric or Newtonian reflector style telescopes without tools!
It's easy...just grab a Bob's Knob collimation thumbscrew and turn. You can even do it while looking through the eyepiece on most scopes. These thumbscrews are also much easier to use with gloves on. And perhaps most importantly, 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.
Part: C8edgBO
Fits: Celestron 8" (20 cm) f/10 SCT with Fastar secondary and EdgeHD optics.
Knobs: Black oxide steel, 12 mm (1/2") diameter
Threads: Black oxide steel
Notes:
- 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 is for dry environments. Lightly oil the knob top and knob serrations periodically as an anti-corrosion measure.
- The factory dust cover will fit normally with Bob's Knobs installed.
Other Information
- Country of Manufacture: United States
Collimate your Catadioptric or Newtonian reflector style telescopes without tools!
It's easy...just grab a Bob's Knob collimation thumbscrew and turn. You can even do it while looking through the eyepiece on most scopes. These thumbscrews are also much easier to use with gloves on. And perhaps most importantly, 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.
Part: C8edgBO
Fits: Celestron 8" (20 cm) f/10 SCT with Fastar secondary and EdgeHD optics.
Knobs: Black oxide steel, 12 mm (1/2") diameter
Threads: Black oxide steel
Notes:
- 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 is for dry environments. Lightly oil the knob top and knob serrations periodically as an anti-corrosion measure.
- The factory dust cover will fit normally with Bob's Knobs installed.
- 3x Factory Secondary Screws
Collimate your Catadioptric or Newtonian reflector style telescopes without tools!
It's easy...just grab a Bob's Knob collimation thumbscrew and turn. You can even do it while looking through the eyepiece on most scopes. These thumbscrews are also much easier to use with gloves on. And perhaps most importantly, 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.
Part: C8edgBO
Fits: Celestron 8" (20 cm) f/10 SCT with Fastar secondary and EdgeHD optics.
Knobs: Black oxide steel, 12 mm (1/2") diameter
Threads: Black oxide steel
Notes:
- 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 is for dry environments. Lightly oil the knob top and knob serrations periodically as an anti-corrosion measure.
- The factory dust cover will fit normally with Bob's Knobs installed.
Other Information
- Country of Manufacture: United States
- 3x Factory Secondary Screws
Bob's Knobs for Celestron C8 f/10 EdgeHD 8" Secondary