The first time Hichcock sees his wife's ghost he runs out into a heavy rain; when he returns his clothes and hair are dry.
Cinzia's position changes between shots hen doctor is watching her sleep on the bed.
Dead woman in the morgue is moving her eyes when doctor visits her.
The lights try to simulate use of candles and (and a match) throughout the movie, but the use of electric lights is obvious.
No sound is heard when Cinzia is screaming from the coffin, yet the coffin is not sound proof and is obviously badly made so it could break easily for her escape.
At the start of the movie cemetery is shown and the man is digging a grave. There is no fog at the cemetery, yet in the shot where he is digging the cemetery, there is, and just around the grave, possibly to conceal reflectors used to make the scene lighter.
The sign to the operating room is written as "operating thearte" instead of "operating theatre"