The popularity of Baader Hyperion eyepieces may be due to their wide range of applications: thanks to their large lens size and threaded mount, they can be used with DSLR cameras. They are comaptible with both fixed focus and variable magnification Hyperion eyepieces: remove the rubber eyecup and you'll find the M43 thread for connection underneath.
To connect a SLR camera, you will need this T2 ring and, depending on the type of camera, an additional T2 adapter.