Baader 1" C-Mount Adapter w/ 1.25" Nosepiece - 18mm Long

The Baader 1" C-Mount Adapter is designed to connect a camera with female C-Mount threads (a common standard for guide and planetary cameras) to a telescope's 1.25" focuser, an off-axis guider, or any other accessory that accepts a 1.25" nosepiece. It also adds a fixed 18mm of length to the optical path.

Yes. The ZWO ASI120MM Mini and many similar guide cameras use a C-Mount thread. This adapter will allow you to insert the camera into a standard 1.25" guide port or focuser. The 18mm length is often helpful for achieving focus in various off-axis guider models.

You have two options. For a standard 1.25" mounted filter, you simply screw it into the internal threads on the end of the 1.25" nosepiece. To use an unmounted filter (27.5mm - 28mm diameter), you place the filter inside the adapter and secure it with the included retainer ring.

Using an unmounted filter with the included retainer ring can save a few millimeters of back focus compared to threading a mounted filter onto the end. This can be critical in imaging trains with very tight spacing requirements. It's a specialized feature for optimizing your optical configuration.

Yes, but you will need a 2" to 1.25" adapter. This Baader adapter has a 1.25" nosepiece, so it will not fit directly into a 2" focuser. You must use the appropriate step-down adapter, which typically comes standard with most 2" focusers.

Yes, this is precisely what this adapter is for. The Baader 1" C-Mount Adapter w/ 1.25" Nosepiece provides a fixed, non-adjustable optical length of 18mm. It serves as both an adapter and a precision spacer.