How can you put mirrors on stage that appear to perfectly reflect the curtain behind? Two way mirrors even block the view half the time. Everyone is quick to explain things with mirrors and black art. Ive been talking to AI and that's even how it thinks illusionists do it.

Research the Million Dollar Mystery.

Look into illusion books by steinmeyer or jc

Steinmeyer's book, "Two Lectures on theatrical Illusion: 'The Science Behind the Ghost' and 'Discovering Invisibility'" will have all the information you need to know. There is also some brilliant material in his "Technique and Understanding".

But one thing to address from your question: There is no way to "perfectly" capture the curtain. There are some very, very good ways but it's never actually perfect.

Doug Henning used mirrors for one of his illusions that was "first surface silvered" for the best possible reflection. It was incredibly delicate and required extra careful handling. It was the only time I was looking right at the gaff but not sure if I was actually seeing it.

Most mirrors are silvered on the back, to protect the delicate finish. The trade off is the transmission of light through the glass ever-so-slightly dims the reflection, and this is what prevents perfection. In most cases it's a non-issue, and the cost is significantly lower.

Https://youtu.be/mX1ea-ZWZ5c?si=vyCGeRTBzqWWZO6o

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