Daniel Radcliffe was allergic to his Harry Potter glasses. He had an allergy to nickel, and they were quickly replaced with hypoallergenic specs. Also, did you know that his glasses had no lenses? This was to prevent reflections from anything happening behind the scenes. The glass lens was added in post-production.
100 Mind-Blowing Reflections Facts
Mirrors facing each other don’t produce infinite reflections. Each reflection will be darker than the last and eventually fade into invisibility. Mirrors absorb a fraction of the energy of the light striking them. The total number of reflections mirrors can produce? A few hundred.