TS-Optics 2" Collar for Receptacles
The adjustment ring fits 2" sockets and is secured in the desired position with three grub screws. This allows you to determine how far an eyepiece or adapter extends into the focuser or diagonal star socket.
A useful addition to this ring is a 2" extension that threads onto the eyepiece filter thread or adapter (see recommended accessories).
The 2" adjustment ring is very popular for astrophotography. The ring prevents a combination of adapters from disappearing completely into the focuser. You get a precise stop and determine the optimal position of the focuser.
The adjustment ring is also often used to prevent eyepieces with a locking slot from tilting when using a ring clamp. The ring reduces the depth of insertion of the sleeve.
You can also make the eyepieces absolutely parfocal to each other with multiple rings, then refocusing is no longer necessary. Or you can set a perfectly parfocal eyepiece to a camera. This allows you to find the object with the eyepiece, focus on it, and then immediately start taking pictures.
||by three metric headless screws - slotted screws
♦ TS 2" locking ring