Baader Planetarium 1.25″ / T2 Adapter (T-Adapter)
This universal Baader Planetarium adapter converts a T2 external thread to a standard 1.25″ fitting, giving you a wide range of options for combining optics, cameras and accessories. The optical path length is just 0.5 mm, so the adapter introduces virtually no change to your projection distance calculation. This makes it ideal wherever the exact optical tube length matters.
The 1.25″ end features an internal M28.5 filter thread, so you can screw in any standard 1.25″ filter directly. No rearranging, no extra parts - the filter simply goes in where it should. The adapter also works as a classic T-adapter for connecting a camera or imaging device to your telescope.
The Baader Planetarium T2 to 1.25″ adapter is precision-machined by one of Europe's most respected manufacturers of astronomical accessories. The build quality meets the standards that Baader users expect.
Key features
- Converts T2 external thread to standard 1.25″ fitting
- Optical path length: 0.5 mm - minimal impact on projection distance
- Internal M28.5 filter thread accepts standard 1.25″ filters directly
- Can be used as a T-adapter for cameras and imaging devices
- Precision-machined to Baader Planetarium quality standards
Technical specifications
| Parameter |
Value |
| Input fitting |
T2 external thread |
| Output fitting |
1.25″ standard |
| Optical path length |
0.5 mm |
| Filter thread |
M28.5 (internal, 1.25″ standard) |
| Manufacturer |
Baader Planetarium |
Who is this adapter for?
This adapter suits anyone who wants to connect a camera, a CMOS or CCD imaging device, or standard 1.25″ accessories to a telescope with a T2 thread. It is equally useful for visual observers who need to add a filter without extra adapters. Because the optical path is so short, it works well in demanding setups where every millimetre of back-focus matters.
Typical uses
- Connecting a DSLR or mirrorless camera to a telescope for astrophotography
- Using standard 1.25″ eyepieces and accessories with T2-threaded focusers or cameras
- Adding a 1.25″ Moon filter or other filters directly to the adapter
- Building compact optical trains where a short back-focus is required
