Bob’s Knobs for Celestron 8″ SCT – Standard

Now there is no more tools needed to make collimation adjustments to your telescope! It’s easy . . . just grab a Bob’s Knob and turn. You can even collimate while looking through the eyepiece on most telescopes. What’s more, you’ll never drop that pesky little Allen wrench or screwdriver in the grass again. Installation is a snap with included instructions, and you can undo the modification at any time.

Fits: Celestron 8 inch (20 cm) f/10 SCT with factory Allen, Phillips, or headless set-style 6-32 collimation screws, with or without Fastar compatible secondary (C8 orange, black, or gray; Ultima 2000; NexStar 8). It is important that you choose the correct style Bob’s Knobs for your telescope. Please note the number and type of screws on your secondary housing before ordering.

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.

Fits: These knobs will fit all C8 models made prior to 2005, and all 2005 and later models EXCEPT those with black Phillips factory collimation screws. The black-screw model requires C8 metric knobs. Check that our screw threads match the factory screw threads before installing.

Bob’s Knobs will provide spacers for knobs installed on the Fastar compatible secondary to raise the knobs slightly for easier use. Please note in the “comments” section of our shopping cart if you need these spacers.These knobs will fit all C8 models made prior to 2005, and all 2005 and later models EXCEPT those with black Phillips factory collimation screws. The black-screw model requires C8 metric knobs. Check that our screw threads match the factory screw threads before installing.

Bob’s Knobs will provide spacers for knobs installed on the Fastar compatible secondary to raise the knobs slightly for easier use. Please note in the “comments” section of our shopping cart if you need these spacers.

• Compatibility:These knobs will fit all C8 models prior to 2005 and later C8 models except thosethat have black Phillips factory collimation screws.
• Check that these screw threads match the factory screw threads before installing.

• Bob’s Knobs for Celestron 8″ SCT – Standard