Bob's Knobs are the BEST option for tool-free collimation.
Simple to fit and easy to use.
Collimate your telescope without an Allen key or screwdriver!
Instructions are supplied but can also be found online as well as useful FAQ.
Images are representative and may not show the exact knob size / threads.
IMPORTANT: Please ensure the Bob's knobs threads and factory screw threads match before installation.
Knobs for C11 f/10 with Flat Secondary Housing and Standard Collimation Screw ThreadsPart:
Celestron 11” (28 cm) f/10 SCT versions (metal or carbon fiber tube) with flat secondary housing and standard collimation screw threads (not for CPC 1100 or EdgeHD). Does not fit the Starizona Hyperstar secondaryKnobs:
Black plastic, 16 mm (5/8”) diameterThreads:
Black Anodised Aluminium alloyNotes:
- Silver factory collimation screws usually have standard threads, but some silver Phillips screws have metric threads. Our hints will help you determine which screws are on your telescope. Make sure the knob threads match the factory screw threads before installing the knobs.
- The factory dust cover will fit normally with Bob’s Knobs installed.
- Celestron 11” SCTs manufactured prior to 2006 have standard collimation screw threads.