Boom mic visible: Near the end of the film, Chief Inspector Uhl is in Prince Leopold's office. In the close-up scene when the two argue, you can clearly view the boom mike, going from one character to the other, in the reflection on the brass table lamp.
Miscellaneous: Choreographer Marleen Pennison, Movement Coach for the film, is incorrectly credited as "Maureen Pennison".
Anachronisms: At the end of the movie, in the train station, electric wires can be seen above the train tracks. These electric wires did not exist in Austria until 1912.
Revealing mistakes: In both scenes at the railroad station, there are overhead wires visible which are of a catenary system used to power electrically powered locomotives and/or passenger cars. The period of the film was prior to electric rail propulsion.
Anachronisms: The ladies of the epoch used to ride in side saddles, not astride the horse, like the heroine does in the castle/forest scene.
Continuity: At around the 20:17 mark, When Inspector Uhl is inspecting the props backstage, Eisenheim has his arms at his side during their conversation. Then suddenly he is facing the inspector at a different angle and his arms are crossed.
Anachronisms: The coins The Illusionist is giving the poor children are bi-metallic coins, i.e. they are made of two different alloys, a ring surrounding a differently colored disc. The technology to make those coins is only a few decades old, and certainly was not available in the 19th century. The coins used are Czech 50.
Anachronisms: When police officers 'offer a drink' to Eisenheim, you can see on the building in the background lightning rod of modern design.
Incorrectly regarded as goofs: When Inspector Uhl is investigating Eisenheim's latest illusion of summoning spirits, one of his aides shows an early turn of the century movie projector portraying a color/sepia based image of a person. Kodachrome film was introduced in 1936. However, turn-of-the-century film was often hand-colorized using stencil methods, the fantasy short subjects of Georges Méliès being a prime example. (In addition, several genuine color film technologies were in use by the early 1920's.)
Revealing mistakes: This is possibly done on purpose. When Norton's character gives the coins to the street urchins, the first coin is visible in his hand before the magic trick occurs.
Audio/visual unsynchronized: When Inspector Uhl finds Leopold to tell him of Sophie and Eisenheim's relationship, Leopold asks Uhl "What where they doing? Touching? Kissing? Fornicating?". His face is only shown when he says "fornicating", but his mouth moves to a completely different word. (see Trivia)
Miscellaneous: Prior to Uhl and Leopold's conversation, Leopold shoots something. When they are talking, it can be seen being dragged off screen (lower right)...and is far too rigid and light.
Continuity: Eisenheim's eye color is different as an adult than it was as a child.
Continuity: Eisenheim's arms during his arrest. He is seen with his arms at his side and crossed at the exact same spot during his arrest at the beginning of the show (current time) and the flashback.
Revealing mistakes: At 1:28:35, you can see the shadow of Eisenheim but at that time he is supposedly an illusion. At 1:29:03, when he is standing, his shadow is gone.
Anachronisms: At the train station, the green trains have large, white lettering boldly printed in Helvetica, a typeface not invented until 1957.
Crew or equipment visible: In a scene in Leopold's office the overhead light banks can be clearly seen at the top of the frame.