
Revealing mistake: When making traps, he's harvesting powder from a spent shell (primer has been struck). (01:05:50)

Revealing mistake: The jaguar near the start jumps onto the bar and prowls along it. It knocks over one glass with some force, which shatters, but the second glass is barely tapped by its foot and it smashes to bits too, when it should just have been pushed out of the way.

Revealing mistake: When Finney is looking for the bike lock's combination written on the wall, the distance between the mattress and that wall (several feet) can be seen. However, the next time Finney wakes up on the mattress, the mattress is against or almost touching the corner, but the mattress was not that close to the adjacent wall. Furthermore, when the Black Phone rings, the mattress is the same distance from the phone as it originally was (which would be several feet away from the wall). (01:04:59 - 01:10:53)

Revealing mistake: As Liam Neeson looks at the money in the bag, he turns it over and it says "motion picture use only" on it.

Revealing mistake: Deacon uses "hidden" food to get the dog to come up to him. The "treat" is largely concealed - but the dog's slobber gives it away. The camera shifts after Deacon's hand goes next to the dog's mouth, giving the impression that Deacon is just petting the dog under his neck. (00:06:35)
Suggested correction: He was feeding him. You can see him eating out of his hand. The food isn't "hidden" You can hear the dog sounding as if he were eating something and his face is in his hand. Those were added sound effects in post. At first glance I got the impression he was giving the dog a treat as they were pals.
Part 1: Based on the circumstances plus Deacon's actions immediately before, during, and after his encounter with the dog, I believe it was a lousy attempt at luring the dog but trying to give the impression there was no lure (food). Deacon did not have food when he came out of his house and wasn't expecting the dog to be there. Deacon even pointed his right fingers toward the dog when he said, " You [are] the one [who has] been gone for the last two weeks." Deacon stoops down and [continued].
Part 2:...makes an effort to point his right hand fingers downward, again giving the impression he wasn't holding anything (food). If feeding a hungry, cautious dog, I think he would have displayed the food in the palm of his hand (what is there to hide if actually feeding the dog?). When "sneaking" the food into the dog's mouth, a small piece can be seen falling to the ground. Deacon holds the dog under his neck, probably to keep the dog from reaching the food that has fallen.
Part 3: (The dog later picks up the piece that fell.) Taking all these odd movements into consideration, I'm sticking with my assertion - Deacon "surreptiously" lured the dog, but his actions were noticeable, thereby revealing what was actually happening. Also, if the dog was missing for two weeks, Deacon would not have been likely to bring food out for the dog that morning. Anyone wanting to view the scene and serve as a tie-breaker, start at 00:06:26, watch Deacon's right fingers @ 0:06:32+.

Revealing mistake: When Bloodsport rescues Ratcatcher 2 from on top of the car, they don't actually dodge the arm coming for them but are going straight through like it's not even there. (01:54:16)

Revealing mistake: When the military security checks Flash's phony badge, the name on the personnel list to the right does not match the fake identity; Barry's false identity is "Rowe, Wesley", but in the list the name "Band, Ryan" is highlighted. This mistake was not present in the theatrical 'Whedon' cut where the name was altered to match. (02:27:05)

Revealing mistake: When Jake is sliding on the floor at the mall trying to grab his retainer, streak marks are visible on the floor from where they practised the shot.

Revealing mistake: The "Anamika Resort" van isn't quite in sync with the road it is supposed to be traveling on. A side view shows the van is traveling straight ahead, but a shift to a front view shows the road behind the van is curved to the right. The same thing happens a little later, except the road is curved to the left. (00:01:19)

Revealing mistake: When Julie is running around the city whilst all the extras are stood frozen, there is a moment where she is walking next to a small park, before beginning to turn right and run down a road. Once she runs onto the sidewalk after running down the road, two girls can be seen stood on the same sidewalk holding hands. The girl on the right can be seen moving her right hand ever so briefly, even though the extras are all supposed to be standing completely still. (00:54:35)

Revealing mistake: In a sudden downpour, "rain" falls vertically, across a single line. (00:18:28 - 00:19:44)

Revealing mistake: Lower-third shots of the aquarium in the background at the Delaware Raceway's sports lounge were often blurred and did not look like they matched full views of the aquarium. (00:36:05 - 00:36:34)

Revealing mistake: The rear of the steer's carcass was on fire and smoldering, but wasn't seconds later in the aerial view. Also in the aerial view, the position of the steer relative to Alexander was different. (00:06:00)

Revealing mistake: A close-up of the Janitor's (Cage's) left cheek shows no moles or obvious blemishes. When the duct tape was shown being put over the cut on the Janitor's cheek, the person's face was not Nicolas Cage's - the "stand in" had moles and other blemishes (age spots?) where Cage does not. (00:04:09 - 00:23:15)

Revealing mistake: When Archie swung the fire extinguisher in front of the woman, it did not look like the fire extinguisher was close enough to strike the woman's body, let alone knock her out. Also, when Archie came out and closed the door, he would have been walking where the woman's body was on the floor. (00:34:05)

Revealing mistake: Ronnie is shown looking through the vertical-rectangular window of a brown door to Joey's hospital room. His eyes are angled to his left, indicating he is looking toward the person in bed to the left of a double room. When Ronnie is standing next to and facing the man in that bed, there's no door with a window behind him that he could have been looking through. There is a windowless white door on an adjacent wall. (00:00:40 - 00:03:42)

Revealing mistake: During one of the chase scenes, an SUV hits a rock barrier and flips over landing on its top. The car spins around, and we see that it is empty. The driver then climbs out as if he was just in the vehicle.

Revealing mistake: The "unnatural seam" (line) across Jimmy's forehead and beyond - as well as the overall appearance of his head - indicates that he is NOT "naturally bald"! His "fake" bald head was not put on nearly as well as those seen in numerous other movies. [The actor playing the character does not have much hair in real life, but he also doesn't have that artifical line across his forehead.]. (00:07:13)

Revealing mistake: It was "raining" when Francesca was driving toward the house, but her vehicle "moved out of the rain" before coming to a stop. Furthermore, when the camera returned to Francesca walking toward the house, it was not raining and the driveway did not look wet. (00:48:53)

Revealing mistake: Based on the size of the dinosaur's back shown behind the 6' high cement enclosure, there is not enough room for the rest of the dinosaur's tail and the enclosure is not high enough to accommodate its neck and head. (00:16:29)