T-rings and mechanical adapters join a camera, filter wheel or focuser to a telescope: a T-ring converts a camera's lens bayonet to a standard thread such as T2 (M42), M48 or M54, and thread adapters, extension tubes and spacers convert between threads and set the back focus a flattener or corrector needs. Match three things before you buy: the camera mount (Canon EOS, Nikon F, Sony E and so on), the thread at the telescope end, and the total spacing, which variable tubes such as the Baader VariLock 46 or SVBONY SV109 and fixed spacers from Player One, ZWO and Pegasus Astro let you fine-tune. Use the type tiles above to narrow the list, and once spacing is set, see Tilt Adjusters to square the sensor.
