This seems a natural artefact from the use of floating point number by real-time rendering. It is an inherit limitation we can't really do much about.
In the sample the issue is amplified even more than with regular rendering by having a camera with a very narrow field of view 1 degree while fields of view of around 90 are more common. This leads to even worse precision artefacts.
To put this in perspective this is like using a camera with a 1.2 meter (1200mm) focal length while a normal lens is around 50mm.
These settings lead to an almost parallel camera. It's better to jus use an orthographic camera for these sort of effects.