GSO Focuser Collimation Ring / Tilt Adapter - For 10" - 16" CC / RC Telescopes with M117x1 Focuser Thread

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- GSO FF672 collimating ring for adjusting the tilt angle of the telescope focuser
- Compatible with the following GSO telescopes: RC10, RC12, RC14, RC16, CC10 and CC12
- Helps ensure sharp images across the field of view, especially for cameras with larger sensors
- Spring-loaded for easy adjustment during imaging sessions
- Easily inserted between the rear cell and the focuser while taking only 15mm of back focus
The GSO FF672 collimating ring helps improve image sharpness when using your 10" or 12" closed-tube GSO Ritchey-Chretien telescopes (of any vintage) or 10", 12", 14" or 16" GSO Ritchey-Chretien telescopes made up to 2016.
Note: GSO truss RCs made from 2017 onward, including all of the current RC telescopes that we sell already feature a focuser tilt adjustment mechanism and do not require this adapter separately. An easy way to tell is to look at screws on the rear of your telescope just around the focuser where it attaches to the OTA. If there are no screws or three pairs of screws, then your telescope can benefit from this accessory. If there are three sets of three screws around the focuser, then you already have this item embedded in your telescope and do not need to purchase this by itself.
The ring allows you to slightly adjust the tilt of the telescope’s focuser so it’s square with the axis of the telescope’s optics. Such adjustments are sometimes required to counteract the small and unwanted tilt of the focuser induced by machining tolerances in the threads of the telescope’s focuser and rear cell. This is especially important when imaging with cameras with larger full-frame sensors.
The FF672 collimation ring fits between the rear cell of your telescope and the focuser/camera assembly. The ring consists of two spring-loaded components with push-pull collimation screws that let you adjust the tilt angle and then lock the position in place.
The telescope side of the ring has M117x1 female threads that connect to the threaded rear cell of the telescope or to appropriately threaded extension rings. The camera side of the collimation ring has M117x1 threads to attach to your focuser. The ring takes only 15mm of back focus.
When installed, the focuser collimation ring will cover the primary mirror collimation screws on the rear cell of your telescope. To ensure enough clearance for these screws should you need to adjust them, you may need to install at least one of the 117mm extension rings supplied with your telescope.
Other Information
- Country of Manufacture: Taiwan
The GSO FF672 collimating ring helps improve image sharpness when using your 10" or 12" closed-tube GSO Ritchey-Chretien telescopes (of any vintage) or 10", 12", 14" or 16" GSO Ritchey-Chretien telescopes made up to 2016.
Note: GSO truss RCs made from 2017 onward, including all of the current RC telescopes that we sell already feature a focuser tilt adjustment mechanism and do not require this adapter separately. An easy way to tell is to look at screws on the rear of your telescope just around the focuser where it attaches to the OTA. If there are no screws or three pairs of screws, then your telescope can benefit from this accessory. If there are three sets of three screws around the focuser, then you already have this item embedded in your telescope and do not need to purchase this by itself.
The ring allows you to slightly adjust the tilt of the telescope’s focuser so it’s square with the axis of the telescope’s optics. Such adjustments are sometimes required to counteract the small and unwanted tilt of the focuser induced by machining tolerances in the threads of the telescope’s focuser and rear cell. This is especially important when imaging with cameras with larger full-frame sensors.
The FF672 collimation ring fits between the rear cell of your telescope and the focuser/camera assembly. The ring consists of two spring-loaded components with push-pull collimation screws that let you adjust the tilt angle and then lock the position in place.
The telescope side of the ring has M117x1 female threads that connect to the threaded rear cell of the telescope or to appropriately threaded extension rings. The camera side of the collimation ring has M117x1 threads to attach to your focuser. The ring takes only 15mm of back focus.
When installed, the focuser collimation ring will cover the primary mirror collimation screws on the rear cell of your telescope. To ensure enough clearance for these screws should you need to adjust them, you may need to install at least one of the 117mm extension rings supplied with your telescope.
- GSO FF672 collimating ring for adjusting the tilt angle of the telescope focuser
- Compatible with the following GSO telescopes: RC10, RC12, RC14, RC16, CC10 and CC12
- Helps ensure sharp images across the field of view, especially for cameras with larger sensors
- Spring-loaded for easy adjustment during imaging sessions
- Easily inserted between the rear cell and the focuser while taking only 15mm of back focus
The GSO FF672 collimating ring helps improve image sharpness when using your 10" or 12" closed-tube GSO Ritchey-Chretien telescopes (of any vintage) or 10", 12", 14" or 16" GSO Ritchey-Chretien telescopes made up to 2016.
Note: GSO truss RCs made from 2017 onward, including all of the current RC telescopes that we sell already feature a focuser tilt adjustment mechanism and do not require this adapter separately. An easy way to tell is to look at screws on the rear of your telescope just around the focuser where it attaches to the OTA. If there are no screws or three pairs of screws, then your telescope can benefit from this accessory. If there are three sets of three screws around the focuser, then you already have this item embedded in your telescope and do not need to purchase this by itself.
The ring allows you to slightly adjust the tilt of the telescope’s focuser so it’s square with the axis of the telescope’s optics. Such adjustments are sometimes required to counteract the small and unwanted tilt of the focuser induced by machining tolerances in the threads of the telescope’s focuser and rear cell. This is especially important when imaging with cameras with larger full-frame sensors.
The FF672 collimation ring fits between the rear cell of your telescope and the focuser/camera assembly. The ring consists of two spring-loaded components with push-pull collimation screws that let you adjust the tilt angle and then lock the position in place.
The telescope side of the ring has M117x1 female threads that connect to the threaded rear cell of the telescope or to appropriately threaded extension rings. The camera side of the collimation ring has M117x1 threads to attach to your focuser. The ring takes only 15mm of back focus.
When installed, the focuser collimation ring will cover the primary mirror collimation screws on the rear cell of your telescope. To ensure enough clearance for these screws should you need to adjust them, you may need to install at least one of the 117mm extension rings supplied with your telescope.
Other Information
- Country of Manufacture: Taiwan

GSO Focuser Collimation Ring / Tilt Adapter - For 10" - 16" CC / RC Telescopes with M117x1 Focuser Thread
