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Bob's Knobs for Celestron C8 f/10 Secondary with Metric Collimation Screw Threads (not for EdgeHD or Hyperstar) # C8met

5.0 (3 Reviews) Read Reviews Write Review
Brand Bob's Knobs
Part Number C8met
Availability available

Product Info

Manufacturer Description

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: C8met
Fits: Most Celestron 8" (20 cm) f/10 SCT made in 2005 and later with black Phillips factory collimation screws that have metric threads. Includes SkyWatcher SCT and non-EdgeHD Fastar.

Knobs: Black oxide steel, 12 mm (1/2") diameter
Threads: Black oxide steel

Notes:
1. Most models with black Phillips factory collimation screws require metric knobs. A few post-2005 scopes have black Phillips collimation screws with standard threads. Here are some hints to help determine which screws your telescope has. Make sure the knob threads match the factory screw threads before installing the knobs. More information is in our Celestron Technical Paper.
2. These knobs will fit the metric Fastar version only if it does not have EdgeHD optics. Scopes with EdgeHD optics require different knobs (Item C8edg).
3. The factory dust cover will fit normally with Bob's Knobs installed.
4. Some telescope versions have a small plastic cover over the factory collimation screws. This cover must be removed and set aside when Bob's Knobs are installed. The cover is cosmetic only and will not affect operation of the scope.

Reviews

5.0 (Based on 3 Reviews) 100% of reviewers recommended this product.
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    1. Guest

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      User Notes:
      Review by shin k.
      1547445906
      Jan 13, 2019

      5.0 NICE!!

      Pros:

      Cons:

      Comments:

      NICE!!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    2. Guest

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      User Notes:
      Review by Roger H.
      1545707321
      Dec 24, 2018

      5.0 Awesome Product

      Pros:

      Cons:

      Comments:

      Cleaned my CPC 800 corrector plate and mirror, so a complete removal. Put the corrector plate back on and it was completely out of collimation of course. Installed Bob's Knobs, and was collimated in just a few minutes. Worked so well I just ordered a set for my 9.25 Edge.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    3. Guest

      Skill Level
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      Time with Product
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      User Notes:
      Review by Joseph R.
      1525403110
      May 3, 2018

      5.0 Bob's Knobs

      Pros:

      Cons:

      Comments:

      Tried collimating using stock Phillips head screws, very cumbersome. Bob's Knobs worked as advertised, quick and easy.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

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      Specifications

      Manufacturer Bob's Knobs
      Additional Information Enabled
      Prism Type 2
      Telescope Aperture Yes
      Eyepiece Field of View Unknown
      Focuser Telescope Type 1 (Yes - Individual Review)
      Barrel Type 7/7/2011 0:00