Corrected entry: When Harry, Ron, and Hermione first go into the forbidden corridor, the pillars that burst into flame for light do not begin until after a person would be walking through the hallway. However, Harry's face is lit when he turns around to see Filch's cat (Mrs. Norris). If the first fire is behind him, why isn't his face in a shadow?
Corrected entry: In the scene right after the Quidditch game (when Harry, Ron, Hermione, and Hagrid are walking through the brick tunnel thing) Ron's scarf is like Harry's - one part over his shoulder, hanging in the back, and the other part of the scarf in front. But when they all walk forward more, and the camera gets closer to them, Ron's scarf is hanging over both shoulders.
Correction: Actually, the scarf always remains on both shoulders, it's just a bit difficult to see when Ron is far from the camera.
Corrected entry: When Harry came back down from when he caught Neville's Remembrall, all the other students cheered and ran towards him. Wouldn't half the students stay back and look mad, since half of them are Slytherin? (00:56:35)
Correction: Not all the students in Slytherin hate Harry.
Corrected entry: When everyone is at the end-of-term feast, Harry has a cast on his wrist, but couldn't Madam Pomfrey (the nurse) have fixed it with magic?
Correction: As witnessed in "Chamber of Secrets" (and in the books), Madame Pomfrey can't just wave a wand and heal serious injuries; she can accelerate the healing process with magic, but it still takes some time.
Actually, Madame Pomfrey herself says "I can mend bones in a heartbeat" (in CoS). It is regrowing bones that is difficult and takes time. Assuming Harry's bones weren't removed in his struggle with Quirrell, the injury would have been fairly simple for Madame Pomfrey to fix. And if Snape can mend Malfoy after Dark magic is used in HBP, surely Madame Pomfrey can fix a cut on Harry's arm.
Corrected entry: When Harry, Ron, and Hermione are hiding from Filch, they find Fluffy, scream, and run away. But when they are speaking of it later, Hermione says something like "Honestly, don't you two have eyes? Didn't you see what it was standing on?" But it never shows Hermione looking down at the trap door when they were face-to-face-to-face-to-face with the three-headed dog.
Correction: The scene cuts frequently therefore she could have glanced down when the camera was not focusing on her face.
Correction: They first see Fluffy while looking down, then travelled all the way up to its face. That's when she saw the trap door.
Corrected entry: When Hermione is trying to figure out the Devil's snare she pulls her magic wand out of nowhere and once she uses it and wants to check if Ron is OK the magic wand disappears.
Correction: She pulled it out of her skirt and put it back in the process of kneeling.
Corrected entry: In the scene when Harry, Ron, and Hermione visit Hagrid, Malfoy is visible through the window. He appears to be eye level with the window and is shown turning and running away. When the camera zooms out later in the film, the same window that Malfoy is supposedly looking through is far too high for anybody to see through without a ladder. He obviously didn't have a ladder or he would have fallen off it when he turned to run away.
Correction: It's not the same window - there's no outside view of it, so we can't be sure how high it is.
Corrected entry: In the first scene Professor McGonagall's broach disappears and reappears several times.
Correction: This may be explained by the fact that she is wearing a cape over her shoulders. As she moves her head, the broach becomes less (or more) visible.
Corrected entry: Hagrid appears at the hut on the rock to fetch Harry on Harry's 11th birthday, which is July 31. The next day they go to London to buy Harry's school supplies, then end the day at King's Cross. But the letter Hagrid hands Harry at the hut (in the book, anyway - and in the film if you stop it to read what Harry doesn't) tells him to report to the train on September 1. What happened to the month of August?
Correction: It is never specified when is Harry's birthday This is a film/book discrepancy.
This seems far-fetched as it is way too well known in the HP universe, the date of Harry's birthday, and it becomes very significant to the plot as to why Voldemort targeted him. A more likely explanation is the film didn't actually say they went out for school supplies the very next day. It was just assumed as that was the next scene we saw. For all we know, Harry and Hagrid stayed elsewhere for a month, and the filmmakers considered it insignificant to show.
Corrected entry: In all the shots of Snape that show the area around his feet, his cloak is either dragging on the floor behind him or gathered about his feet showing that it is quite long. However, after he wishes Harry luck in the Quiddich game against Slytherin, when he walks away the cloak is short enough in the back so Harry can see his limp from being bitten by Fluffy.
Correction: He could have had more than one cloak. So when he got the injury on his leg, the other cloak could have gotten ripped so it needed repairing. That meant that he had to wear a different cloak until his other one got mended.
Corrected entry: When Harry visits Gringotts, and is seen at vault 713 he is carrying 3 bags (presumably money he has just taken from his own vault). When he has picked up some supplies, and is just about to go to Olivander's, he and Hagrid are only carrying boxes. (00:23:25)
Correction: Maybe Hagrid was carrying them in his coat, or maybe they had spent almost all the money, so they didn't need to carry the bags.
Corrected entry: At the end of the movie, when the train is leaving Hogwarts, where is the big lake that they crossed in boats in the beginning of the movie? If you look at Hogwarts there is clearly no lake around it.
Correction: There's no lake around the castle - it's on the south side. First years just cross the lake because it's tradition.
Corrected entry: When the Slytherins and Gryffindors have their first flying lesson, there is a girl wearing another house's uniform. <
Correction: It isn't specified in the movie that only Slytherins and Gryffindors are in this class. This is more of a movie/book discrepancy.
Corrected entry: How come Hermione is so confident that she'll get into Gryffindor? On the Hogwarts Express Train, she is already wearing a Gryffindor tie (red and yellow) before arriving at Hogwarts or being sorted into houses.
Correction: She is wearing a black tie with Hogwarts' crest.
Corrected entry: At the beginning, Dumbledore is taking out all of the street lights, from one shot, the car in right is in the second house, but in the next shot, the same car is in the first house. (00:00:55)
Correction: The first shot of Professor Dumbledore taking out the lights is from behind him, looking over his left shoulder. He obscures the first car (a yellow one parked in the drive of what appears to be no. 1 Privet Drive). The second shot of the same scene is from some 50 yards in front of Dumbledore, looking towards him, and shot looking down from the height of a lamppost. The lamp obscures the second car (a blue one, parked in the drive of no. 2). Both cars can be seen when Dumbledore and McGonnagal walk towards Harry?s house.
Corrected entry: When Harry buys all the sweets from the cart on the train he places them on the chair beside him. But there are clearly more sweets on the chair then there were on the trolley.
Correction: He simply gave the woman a handful of money. If he had more money than there was candy, the lady could simply get (or magic) more.
Corrected entry: When Hagrid picks up the Philosopher's Stone from Gringotts, he tells Harry "best not mention this to anyone". But as soon as Harry becomes suspicious about Snape, he begins discussing the fact that Hagrid emptied the vault in full earshot of all and sundry, at the dinner table.
Corrected entry: Dudley is supposed to fall into the water in the Reptile House, which is obviously the one at London Zoo, yet he arrives back at his home in Surrey still shivering and wet. He would surely have dried out a bit on the journey home?
Correction: It's possible to get from London Zoo to within the borders of Surrey in a very short space of time - we never find out exactly where the Dursleys live.
Corrected entry: If Harry, Ron and Hermione can walk undetected under the invisibility cloak, why can't Harry walk with the lamp underneath it when he is going to the restricted section of the library? Surely he wouldn't have to hide the light if he did so, reducing the risk of being spotted?
Correction: Two thoughts - one is that he might worry about it catching fire, the other is that it might work on a "one way" system. Light can go into the cloak, so he can see through it, but light can't escape out, so no-one can see him, and similarly the light from the lamp can't escape. If anyone has an official description of how the cloak works, I'll gladly hear it!
Corrected entry: This must always be a risk when working with child actors and filming out of sequence, but Daniel Radcliffe's voice obviously started to break during filming. It was most noticeable during the scene in the forest when his voice went from high to low to high again (and again, and again...)
Correction: Only natural - voices don't break evenly. I think they filmed it mostly in sequence to avoid any major shifts.
Correction: It's the light from the open doorway.