After Jack has escaped from the gallows with Will, Commodore Norrington comes up to Will and puts his sword onto Will's right shoulder. When we see a close-up of Will, you can see that the blade has switched to his left shoulder.
"Bob's your uncle" the British catch phrase, meaning all will be well or all will be taken care of is thought to refer to Prime Minister Lord Robert Salisbury who appointed his nephew to be Secretary of Ireland in the 1890s.
The word "Scallywag" which is used to refer to a fellow pirate, is in fact only invented in the 19th century (after the American Civil War as a name for white southerners who collaborated during the reconstruction).
HMS Dauntless and HMS Interceptor are shown flying the British Blue Ensign. Prior to 1864, the color of a Royal Navy vessel's ensign was determined by its posting. The color of the Caribbean squadron's ensign was red, as should have been the Dauntless' and Interceptor's (blue was the color of the south Atlantic, Pacific and Indian oceans).
All the Royal Navy officers seen are wearing uniforms that would not be introduced until 1747.
Norrington's orders were signed 'George R', indicating King George I of England. This dates the film to between 1714 and 1727.
The films place the Governor's Mansion in Port Royal, but that city was almost entirely destroyed by an earthquake in 1692, at which time the capitol of Jamaica was moved to Spanish Town. The signature of George I on Norrington's orders dates the films to at least 22 years later.
At least twice during the movie, the left side of the ship is referred to as "port" (as in, "drop the port anchor"). "Larboard" was used until the 19th century when referring to the ship, and "port" was only for directions. "Hard a-port" or "turn to port" would have been used, but nothing referring to the port side of the ship until the 1800s.
Both the Interceptor and the Dauntless are painted in the Nelson Checker - black and yellow bands with black port-lids. This scheme dates to Admiral Nelson's command of HMS Victory in 1803. While Nelson's ships were repainted in this scheme it did not become widespread until after the Battle of Trafalgar, 1805. Both before and after this Captains were free to, and did, paint their ships as they saw fit.
When the young Will Turner first comes to and grabs the young Elizabeth's arm, she assures him by saying "It's okay." Although the origin of the word "okay" is unclear, it was not used until at least a hundred years after the early seventeenth century when the film is set.
At the beginning of the scene when Will Turner is going to break Jack Sparrow out of the prison cell, when Jack is lying on the ground talking to Will, you can see a modern shoe print below Jack's right arm.
We are repeatedly told that the cursed crew of the Black Pearl have been on their quest for ten years. However, the ship's first appearance, in the opening sequence, must take place at least twelve years earlier: the Royal Naval ship in the opening sequence is carrying the arms of William III (1689-1702), whilst a glimpse of a document signed 'George R' indicates the bulk of the film takes place under George I (1714-27).
At Commodore Norrington's promotion ceremony, the troops are given the command "right about face", which they proceed to execute. As the camera changes angles they have not completed the command, but you never hear the sound of their feet completing the last step of the maneuver.
Captain Barbossa states that the pirates cannot feel anything on their skin since the curse was put upon them. However, in the beginning the Pirate Ragetti can feel the coals that Elizabeth drops on him claiming that they're "Hot Hot". If what Barbossa says is true, the coals shouldn't have affected Ragetti.
When he first shows up in the movie bringing the sword to Governor Swann, Will Turner is almost clean shaven (just a trace of a little mustache). His next scene, at the blacksmith shop - which in the movie happens at the same day, maybe an hour later - Will has a little goatee and almost full mustache.
At the beginning when Jack is standing on the sail of his sinking boat, he prepares to step onto the dock by raising and extending his right foot out. The next shot shows his left foot taking the first step onto the dock.
In the beginning of the movie when Elizabeth awakens from her dream and her father begins knocking on her door, the two maids come in. One is wearing a red dress, the other a print dress thats a beigeish color. There positions switch alternately. In the first shot, the one in the beige dress is holding the box and the red dressed one is opening the curtains; however, in the next shot, red dress is holding the box and beige dress is opening the curtains.
When the Black Pearl is attacking Port Royal, Will Turner is fighting the pirates with his vest and shirt undone. When the pirate knocks him out at the end of the scene, and he hits the ground, his shirt and vest are almost completely buttoned again.
When Will and Jack are fighting in the blacksmith's shop, right after Will pulls out the hot sword, the donkey starts the gears turning. In the next shot, the gears aren't turning. The shot after that, they are.
When Jack and Will board the Dauntless after walking under the water with the rowing boat over their heads, by the time they have climbed onto the deck and announced that they are taking over the ship their clothes are bone dry.
In the governor's mansion, when Ragetti and Pintel are chasing after Elizabeth, Ragetti is carrying a lighted torch in his hand. When the ashes and coals are dropped on him, he is still holding the torch as he tries to brush the ashes off. In the next shot, as he and Pintel exit the room, he is no longer carrying it. When he appears at the banister and jumps off the landing to corner Elizabeth, the torch is back in his hand.
When Elizabeth's hand is cut and her blood is spilt on one of the Aztec Gold pieces; there is an obvious stain on the Aztec Gold piece. When Barbossa picks up the same piece and dangles it in front of Elizabeth, the blood stain is still there...in the next shot of the piece...there is no blood on it.
When Jack is talking to the two guards on the dock, in the background you can see a man rowing a boat towards the ship by the cliffs. As the camera switches back and forth between the guards and Jack, you can see the progress of the rowboat. However, at one point the boat suddenly disappears, but wouldn't have had enough time to have rowed out of the camera's view.
During the fight between the pirates and Norrington's crew at the cave, one of the two guards from the dock had been killed just moments earlier is now alive again and fighting the pirates on the deck.
When Jack Sparrow first arrives, the sky is full of white clouds and light blue sky, implying that it is midday and the sun is high, however when we see the close-ups of Jack, the clouds have a deep yellow tint to them as if it is sunrise or sunset.
In the opening scene Governor Swann approaches young Elizabeth on a crowded deck and asks her to accompany Will. We can see his body being picked up and moved by sailors. In a later shot, we see Elizabeth standing on an empty deck looking at young Will's body laying on the deck.
When Jack escapes from the brig on the Black Pearl and stands
on the side of the ship, the rope netting is on his left. Then when there is a close-up of him taking the rope from the swinging pirate, the rope netting is on his right-hand side, then switches back. This is because the geography of the boat did not quite work out and so the close-up shot was reversed later in editing.
When Barbossa abandons Elizabeth and Capt. Jack on the island, Jack is wearing boots when he dives off the plank, but the boots disappear when he hits the water. The boots reappear when he grabs his sword and pistol and pushes off the bottom.
When Elizabeth and Jack are being made to walk the plank, Jack dives in to retrieve his scabbard and as he swims to the bottom his feet are bare. However, when he goes to push off the bottom toward the surface, he is wearing boots.
When Elizabeth takes the medallion out of the secret hiding place, her fingernails are short. When Captain Jack saves her from being shot during the battle between both ships, her nails are long and manicured.
In the opening shots of young Elizabeth singing at the front of the ship, the posts on either side of her have rope on them (wrapped around them). Moments later, the post to her right has no rope wrapped around it or hanging from it.
A shot opens with the full moon prominent in the frame. The moon is crossed by the sails of The Black Pearl at an angle that indicates that the moon is almost straight overhead. We pull back to show the ship gliding past, and when it has, we are looking at the horizon, where we see the full moon very close to setting.
The young Elizabeth Swann takes a pendant from the neck of the young Will Turner. At first sight the pendant is on a thin string or a fine chain. Minutes later when Elizabeth examines the chain, we see a significantly heavier chain in the palm of her hand.
In the post-credit scene, Jack the monkey is seen swimming in the water at Isle de Muerta. He jumps from the water on to the chest. When the camera switches from the water to Jack on the chest, Jack is completely dry.
Just as Jack says, "On deck, you scabrous dogs," to the very left edge of the screen over Jack's shoulder is a grip crew member with a tan cowboy hat, white short sleeve tee shirt and sunglasses, just standing there looking out to sea.
When the Commodore and Jack are discussing how to attack the cave and the Pearl, the movie pans out to show the two small boats. The boat that has Jack and the Commodore in it, if you look to the right in the water you can view a green diver's fin that comes out of the water.
The Royal Navy did not station any 100 gun ships of the Line in the Caribbean. The ships were simply too large and deep drafted to be of much use in those waters. The English bases in the area were incapable of supporting ships that size. And the Royal Navy only had six such ships world-wide at the time of the film.
When Jack first sails into Port Royal, there is a shot from behind Jack, looking toward the front of the boat, and there is land clearly visible across most of the field of vision. After Jack jumps down, you see him (from a side shot) begin walking toward the back of the boat. The next shot is again looking towards the boat's front from the stern (which cannot be disputed because Jack is completing the strides from the previous shot) and there is no land visible at all.
The chest of cursed Aztec gold, which Cortez was said to have taken from Mexico, depicts four representations of the primary image of the Sun Gate from the Tiahuanaco civilization, outside La Paz, Bolivia.
Elizabeth Swann's maid fills a bed warmer with red-hot coals and then places the warmer at the feet of Elizabeth, who is lying in bed. That's not the way bed warmers were used. They held warm, not red-hot, coals, and were placed in bed before one turned in and removed before the sleeper lay down. If used as shown in the movie, they would have barbecued one's feet.
When Jack and Will walk underwater towards the ship they intend to steal, they are holding an upturned rowing boat over their heads to trap air, allowing them to breath. This would be impossible in real life, since not only is the boat made of wood (which floats), but due to the upthrust of the trapped air, Jack and Will would need to weigh several tons between them to keep the boat down.
Capt Jack uses The Interceptor's wheel to swing Wil Turner out on the boom after they have taken her from the British. Turning the wheel of a multi-tonne ship hard side-to-side would not result in sufficiently rapid change of course to swing the boom from side-to-side.
Shortly after Jack rescues Elizabeth Swann from drowning, he is handcuffed. However, when he flies through the air and lands on the cargo boom, his arms flail around unchained. Then when he flies down the zip wire, the 'chains' are obviously too long.
When Elizabeth is on the Black Pearl, she holds the medallion over the water in order to prove that the pirates actually wanted it. Though the pirates can walk underwater and suffer no ill effects, they still jumped when she pretended to drop it because of the instinct to prevent it from being lost. Breathing underwater is not a natural human state, and they likely still think mostly as humans. Furthermore, a tiny piece of gold adrift in the ocean in the middle of the night would not be easy to find, even for the undead.
Captain Barbossa, after telling Elizabeth to remove her dress before being deserted at the island, lifts the dress up to his face and says, "Still warm." The pirates are not supposed to feel anything, but it is possible that he was being facetious.
Will has a tattoo on his wrist which is visible in some shots. We are not told that Will is free of tattoos and the fact that *we* know it to be an "elvish" nine is of no consequence - it's just a pretty pattern.
Throughout the entire movie we are lead to believe that whoever possesses one of the cursed pieces of gold becomes one of the undead. So the question becomes how come Elizabeth wasn't part of the undead when she possessed one of the pieces of gold all those years? Answer: It's only people that take the gold from the chest directly. Otherwise Will would have also been undead as a boy since his father passed it to him. Jack only became undead towards the end because he took one directly from the chest.
During the battle scene at Isla de Muerta, Commodore Norrington and his men on the rowboats does not hear the gunfire on board the H.M.S. Dauntless. However, when the wounded sailor on board the Dauntless rings the bell, we see a shot of Norrington looking towards the ship then a shot of the ship with gunfire clearly audible and echoing through the night. If it was audible at this point from this distance, then it should have been audible since the first shots were fired and thus Norrington should have noticed them without the need of the bell.
When holding Elizabeth hostage, Jack calls Norrington by his name and rank. Yet, while he had just heard Elizabeth calling Norrington "commodore", nobody says his name. It is evident they just met, so how did Jack guess his name?
While being held captive by Jack at their first meeting, the gold medallion is clearly visible hanging around Elizabeth's neck. Jack saw it and commented on it! He should have just grabbed it during his escape.
When Pintel and Ragetti are rowing (dressed as females) towards the Dauntless, Ragetti knocks Pintel's umbrella away. When Ragetti threw his away, he turned into a skeleton progressively, as the moonlight fell on him (meaning that while the umbrella's shade was on half his face, only the exposed half was skeletal.) However, Pintel stays entirely human until the umbrella is completely out of his hands, and then he turns into a skeleton in one frame.
After Will And Jack commandeer the Interceptor, the ship is
viewed from above, sailing on a beam reach (a point of sail in which the boat is at 90 degrees to the wind). When Jack knocks Will off the ship with the boom, he jibes the boat, causing the sail to shift positions suddenly. In order to do this from the previous position, he would have had to turn the ship almost completely around. This would have taken well over a minute. Jack did this in less that three seconds. The sail is also filled to the wrong side while it sweeps Will off the deck.
Towards the beginning of the film, Jack is running handcuffed from the British Soldiers. At one point he uses his handcuffs to slide across a rope like a zip-line. However, it would be physically impossible for him to get his handcuffs around the rope without removing the handcuffs or detaching the rope. If you look closely or watch in slow motion you'll see in this scene one if Jack's hands is removed from the cuffs so he can quickly fling it around the rope and grab it with his hand. The next scene shows him zip-lining down the rope with both hands cuffed.
There are several points during the sword fight in the blacksmith shop where there is an obvious stunt double for Will, such as when he somersaults over the pole - the double has a much higher hairline than Orlando Bloom.
During the sword fight in the blacksmith shop between Jack and Will, when they are seen to jump from roof rafter to rafter, they are actually jumping over unfinished plywood with taped marks in place of rafters.
When the Governor opens the windows of Elizabeth's room and says "It's a beautiful day," in the view out the window is a hut that appears to have smoke coming out of it but it can be seen that it is a still picture and the smoke is not moving.
When the Pearl is chasing the Interceptor both ships go full wind. Therefore, flags on both ships are flown back as though the ships are propelled by something other than the wind. When a ship is driven by the wind, the flags will be flown in the direction of the wind which in full wind will be from stern to bow.
At the battle on the Dauntless, when Norrington boards and fights a skeleton, a man can be seen in the background waving his sword. If he was fighting someone, their shadow would've been cast on the ground and visible to us.
When Jack and Will are fighting at the Blacksmith's, right after the eunuch conversation, Will jumps/flips/rolls over the turn-style being pulled by the donkey. However, you can tell that this wasn't Orlando Bloom, but a stunt double.
When Jack and Will are completely submerged underwater, the camera shot changes to their faces which appear above water and have breathable oxygen holes. the shot shows the boat under water with no way to breathe so this is a mistake.
HMS Interceptor is blow up when a pirate is seen lighting a trail of gunpowder that leads to pile of gunpowder kegs. The gunpowder that is used is obviously modern smokeless powder as evidenced by its slow burn rate. Modern gunpowder wasn't invented until 1875 so only black powder would have been available. Black powder 'flashes' and would burn at a rate many times that which was shown.
At the end of the film Jack is about to be executed. The court crier reads aloud the charges against Jack, and then concludes that he is to be "hung" by the neck until dead. Proper English dictates that he would be "hanged" by the neck until dead.
When Jack and Barbossa are fighting in the cave, Barbossa seems surprised that Jack is also cursed. Being a skeleton in the moonlight, he rolls a cursed coin between his fingers and says that he couldn't resist, hinting at an earlier scene, where he took a few coins from the chest, threw them back, but secretly kept one. Now, Barbossa saw him take the coins, but did not notice that he kept one. However, even if he hadn't kept it, he would still be cursed, since he didn't return the coins together with his blood. Barbossa, being well aware of the rules of the curse, would be fully aware of this and shouldn't be surprised that Jack is cursed.
When Jack shoots Barbossa at the end of the film, Barbossa uses both hands to rip open his shirt to see the gunshot wound. When Barbossa falls, an apple rolls out of his hand, but when he rips his shirt open there's no apple.
At the end, when Will is helping Jack escape the gallows, the take a long piece of rope and use it to slam two soldiers into a concrete pillar. From the forward shot, we see the one on the right get his hat knocked off, then the shot from the back shows (as he gets slammed into the pillar and is now perspectively on the left) his hat still on. Then the shot switches to the front view and his hat is once again off.
When the Black Pearl engages the Interceptor the pirates ignite the powder kegs causing the Interceptor to explode completely. The explosion is followed by an areal shot of the island and a clear view of the Black Pearl and the Interceptor fully intact, mast and all, though it just exploded. It is not seen in the next shot of Elizabeth Swann walking the plank.
In the scene near the end when Jack, Will, and Elizabeth are leaving the cave on Isla de Muerta, the chest of Aztec gold has the lid closed. Just before the credits roll and the monkey goes to take one of the gold pieces, the lid is partially open, allowing him to take the gold.