Eyepiece projection is a method of capturing images through a telescope’s eyepiece using a camera with its lens removed, and is normally used where high magnification is required, for example when photographing the planets or features on the Moon.
One of the issues associated with this method of astrophotography is attaching the camera adequately to the telescope, ensuring that it is accurately aligned with the eyepiece.
There are several mounting systems that clamp onto the eyepiece body, but some eyepieces have a suitable thread built into their top to take an adaptor to produce a very solid and perfectly aligned threaded attachment point.
The Baader Hyperion zoom lens has such a thread and would be a good choice. However, this method of photography can be quite fiddly.
You would probably achieve better results using a high quality 3x Barlow lens like the Explore Scientific 3x Focal Extender, Celestron X-CEL LX 3x Barlow or a Televue 2.5x Powermate.
For more advice, read our guide on how to attach a DSLR camera to a telescope.
Email your astronomy queries to Steve atscopedoctor@skyatnightmagazine.com and they could get answered in a future issue of BBC Sky at Night Magazine.