Continuity mistake: While initially walking on the train, we can see that the bottom of Regan's feet are filthy dirty, almost black on the bottom. She takes a few steps off-screen, and we now see her feet are cleaner. (00:40:00 - 04:01:00)
Continuity mistake: At the market, Lee picks out five pieces of fruit (one apple and four oranges?), tears a produce bag off, and walks away. He takes a few steps off-screen, and he is next seen going around an end cap and walking down an aisle, with nine pieces of fruit in the produce bag. (00:01:36)
Revealing mistake: Emmet held a cigarette lighter, displaying a fairly high flame for a long period of time and even held the lighter sideways in his palm without burning his hand! If it were a real flame, he most certainly would not be able to hold it lit very long and would have burned his hand. (00:24:25 - 00:25:25)
Factual error: 1. Turntables used by radio stations have no repeat play function; they are strictly manual operation. 2. Even if they did, continuous play of one 45rpm record would have eventually elicited a skip, and later the complete wearing through of the vinyl by friction of the needle. (01:25:40)
Revealing mistake: The "baby" looked quite "rubbery" at times and its limited movements (even motionless) and lack of sound are indicative of a "fake" baby (doll) most of the time. The baby was mostly kept covered in some kind of box and did not even cry when the mother was running with it (while in her arms or in the box). (00:14:35 - 00:20:30)
Suggested correction: This is not really a "revealing mistake." Fake babies are used in movies all the time. Due to the complexities of filmmaking, it is simply impractical and impossible to use real infants for most scenes. Child safety and labor laws strictly limits how long a baby can be on set. A fake baby may or may not look "rubbery" but that is what they had to work with.
Your correction is precisely what makes it a revealing mistake. Explaining why a mistake occurs doesn't invalidate the mistake. You could only argue that it doesn't look fake or a real baby was used, but since that's not the case, the mistake stands.
A "mistake" is an unplanned and/or unwanted circumstance. Obviously using a fake baby was an intentional decision. At best, this should be classified as a "Deliberate Mistake."
This very website defines "revealing" mistakes as: "Anything which gives away filming techniques, such as stunt wires being visible, or glass smashing before anyone goes through it." (And I could be wrong, but I believe the definition used to be even broader.) An obviously fake baby falls under that umbrella, and always has. You simply can't argue that it's not a revealing mistake by the rules of this site just because it was a deliberate choice by the filmmakers. Heck, even under your strict definition of mistake (which is very problematic, because it doesn't really account for plenty of things that 99.9% of people would commonly consider "movie mistakes"), it's still a mistake, since the filmmakers wanted people to think it's real, and we obviously don't - ergo an unplanned circumstance.
