Bob's Knobs for GSO made 8" Ritchey-Chretien Secondary (Astro-Tech, TPO, Apertura, Orion, iOptron)
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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: AT8RC
Fits: Astro-Tech, GSO, iOptron, MallinCam, Orion (US), and TPO 8" f/8 RCT secondary (solid or truss-tube)
Knobs: Black plastic, 16 mm (5/8") diameter
Threads: Stainless steel
Notes:
- If the dust cover cannot be installed because of knob height, you can use a shower cap in its place.
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: AT8RC
Fits: Astro-Tech, GSO, iOptron, MallinCam, Orion (US), and TPO 8" f/8 RCT secondary (solid or truss-tube)
Knobs: Black plastic, 16 mm (5/8") diameter
Threads: Stainless steel
Notes:
- If the dust cover cannot be installed because of knob height, you can use a shower cap in its place.
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: AT8RC
Fits: Astro-Tech, GSO, iOptron, MallinCam, Orion (US), and TPO 8" f/8 RCT secondary (solid or truss-tube)
Knobs: Black plastic, 16 mm (5/8") diameter
Threads: Stainless steel
Notes:
- If the dust cover cannot be installed because of knob height, you can use a shower cap in its place.
Other Information
- Country of Manufacture: United States
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Bob's Knobs for GSO made 8" Ritchey-Chretien Secondary (Astro-Tech, TPO, Apertura, Orion, iOptron)