GSO Focuser Collimation Ring / Tilt Adapter - For 6" and 8" CC / RC Telescopes with M90x1 Focuser Thread

Our #: PAPI-GS-FF670
Mfg #: FF670
Our Price: $84.95
Free shipping for this item in the US
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Out of Stock
Availability: Expected mid-April

Quick Overview

  • GSO FF670 collimating ring for adjusting the tilt angle of the telescope focuser
  • Compatible with the following GSO telescopes: RC6, CC6, RC8 and CC8
  • 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

Product Details

The GSO FF670 collimating ring helps improve image sharpness when using your 6” or 8” GSO Ritchey-Chretien or Classical Cassegrain telescopes. 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 FF670 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 M90x1 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 M90x1 threads to attach to your focuser. The ring takes only 15mm of back focus.

Important note: We have had a couple of cases in the past where this item did not work with M90 extension tubes from those customer's GSO-made (but not GSO branded) scopes. In both cases, it turned out that the issue was with the extension tube threads that were slightly out of spec (even though they did work perfectly on the scope) and not with this tilt adapter.

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 90mm extension rings supplied with your telescope.

Other Information

  • Country of Manufacture: Taiwan