(at around 1h 35 mins) While Rose and Jack are having sex in the Renault, we can see Rose's hand leaving a print on the rear window. Immediately after that, the camera moves inside the car, and it is clearly seen that the handprint is not only in a lower part of the window, but also in a different shape.
(at around 1h) Jack takes Rose and Molly's arms to escort them to dinner. They start walking, but in the next shot, they are still standing apart.
After the drawing is completed and Rose has dressed, she is not wearing her engagement ring. Several scenes from then until the final sinking, show her left hand devoid of the ring. However, when she is underwater after the stern has sunk, a scene shows the violent suction of the water pulling that ring off her finger and flying away in the vortex.
When Jack and Rose first meet at the stern, Rose is clearly wearing jeweled, slip-on shoes and black stockings. However, when she is lying on the deck after Jack rescues her, she is wearing red lace up boots instead.
Young Rose's shoes are clearly off in one wide shot as she stands on the railing of the ship. As we cut to her before she turns around, when we can see her entire body, we can clearly see in two shots her toes outlined by black nylons clutching the rail, and NOT her heels as seen previously in other shots before and afterward when she slips on her gown as Jack pulls her back over the rail to safety.
(at around 1h 29 mins) Shots of the Titanic steaming at night and just prior to hitting the iceberg show a great deal of lights on the foredeck and from the cabin windows on the front of the ship facing the foredeck. In reality, Atlantic liners would not have had so much light showing forward of the bridge as the glare would have interfered with navigation at night.
(at around 46 mins) The blue diamond "Le Coeur de la Mer" is stated as having 56 carats which would put its weight at 56 * 0.2 = 11.2 grams, which would be much too light for a diamond this size.
(at around 1h 50 mins) Jack is held prisoner in the Master-at-Arms' office, which is depicted as having a porthole. On the Titanic, this room was an interior room and hence would not have had portholes.
Passengers were not allowed at the forecastle head, or bow. The sign that declared "Passengers Not Allowed Beyond This Point" was mounted on the leeward side of the forward breakwater (both port and starboard), and was missing in the film.
(at around 27 mins) The Titanic's middle propeller was powered by a Parsons steam turbine, which ran off expelled steam from the two main reciprocating engines. This meant that the turbine could only run when a full head of steam had been generated. It would not and could not have been used for maneuvering in port. Hence, the middle propeller would have been stationary when starting away from the dock.
(at around 1h 25 mins) Although her fingers partially obscure it, the coin that Rose pays to Jack is generally agreed to be a Barber dime, minted 1892-1916, not a modern dime, as some viewers have incorrectly asserted. The Barber dime is distinctive because the portrait of Liberty on the head of the coin faces to the right, not the left.
Some artifacts recovered from the Titanic's wreckage included a number made of paper, which were saved because of their storage in leather bags or such; it is therefore possible for Jack's sketch of Rose to have survived as shown.
(at around 36 mins) When Rose is considering jumping off the ship toward the beginning of the movie, she is not wearing the necklace she had on at dinner. Her hair is also different. In fact, there was a scene that was cut from the movie where Rose runs back to the parlor suite, tears off her necklace, lets her hair down, and in a fit of rage, destroys some of the items in her bedroom before running to the stern to attempt suicide.
(at around 1h 35 mins) When the ship is bearing down on the iceberg, the officer orders the helmsman to put the helm hard to starboard and later hard to port. In each case the helmsman appears to do exactly the opposite. However, prior to the advent and mass popularity of the automobile, a ship's wheel was rigged such that to turn the ship left (port), the wheel was turned clockwise (or as we would consider it, to the right). It was only after a generation of drivers had grown up driving cars that the shipping industry began rigging their wheels to conform.
Although the Titanic's fourth smokestack was not an exhaust avenue for the ship's engines, it was used as an outlet for the Titanic's massive kitchen. Since the Titanic used coal stoves, some smoke would have been coming out of the fourth smokestack. In one of the flyover shots of the ship, it is possible to see that most of the top of the fourth smokestack is sealed.
(at around 10 mins) Rose's drawing that's found and cleaned with great care and was in the safe is a noticeably different version than the version Jack sketched (at around 1h 28 mins). Notice how the face, lips, eyes, hands, and overall picture is much different from Jack's sketch.
Near the end of the movie, when the Titanic is nearly vertical, a man, who is falling off the ship, hits one of the capstans and it bends, showing that it is clearly made of rubber. It is mentioned in the documentary the filming set had a lot of foam props for safety.
(at around 1h 30 mins) After Jack and Rose take a shortcut through the engine room to escape Lovejoy, there is no soot on Rose's pale blue gown.
(at around 2h 40 mins) Rose's hair defies the law of gravity when she is atop the sinking ship. Her hair should be hanging down or at least moving in the cold wind as the scene suggests, but it is perfectly still and horizontal in respect to the sinking ship.
(at around 31 mins) During the ship's flyover shot, if we look closely, we see a lady in a burgundy coat walking, but her feet aren't touching the ground, she is floating.
It would be unlikely that Margeret Brown would have her son's formal wear in her cabin. On trans-Atlantic voyages in the early 20th century, first class passengers often had several steamer trunks of assorted items. Those that were filled with items not essential would be marked "not required for voyage." Brown's son's clothing would be labeled such.
When Rose makes her way through the freezing water to rescue Jack, she doesn't once react in pain to the freezing water, though she does give a Oh! when she first goes into it.
Why is Murdoch in the final scene? He wasn't friends with Rose and Jack. And technically he didn't die in the sinking. He shot himself.
(at around 34 mins) Rose mentions Sigmund Freud's ideas on the male preoccupation with size to Bruce. Freud did not publish the work relating to this until 1920 in "The Pleasure Principle." Also, up until 1919, Freud relied solely on data from females.
(at around 40 mins) [acknowledged by James Cameron] Jack claims to have gone ice fishing on Lake Wissota, near Chippewa Falls, Wisconsin. Lake Wissota is a man-made reservoir which wasn't created until 1917.
The underwater shots of the propellers are incorrect. The famous photo of the ship in dry dock and the men standing under the propellers clearly shows that the propellers were bolted together with giant nuts as was the practice at that time. The underwater shots of the propellers show smooth metal (no bolt heads/nuts) suggesting welding, which were not available until WWII.
(at around 3h) When Rose is arriving in New York, she looks at the Statue of Liberty, which is the same color as now (copper green). But if you visit the Statue of Liberty, we'll find a plate telling us that the original color was brown, and it took over 35 years for it to change color. The Statue of Liberty was established there in 1886, so in 1912 it should have still been partly brown. Also, the flame was replaced in 1986 (for its 100th anniversary) with a gold flame. The film shows the Statue holding a torch with a gold flame, not the original.
(at around 25 mins) When Jack and Fabrizio are running to board the Titanic, Jack has a rucksack, standard issue Swedish Army gear, circa 1939.
(at around 2h 50 mins) After the Titanic sinks, a lifeboat returns to look for survivors. The officer in the boat is shouting and his voice is echoing; for it to echo it would have to hit a surface and bounce back but because it's the middle of the Atlantic, there is nothing to echo back from.
(at around 1h 40 mins) After the collision with the iceberg, the Captain orders all engines stopped. However, the telegraph bells are only heard once, meaning that the other engine would still be in full reverse, which clearly isn't.
(at around 1h 14 mins) During the church service, the pianist can be seen hitting the keys, but not moving his hands to change chords or hit any other notes, higher or lower.
(at around 49 mins) While on deck, Jack asks Rose, "Do you love the guy or not?" The shot changes to show Rose's reaction. Jack's jaw can be seen moving, as if he's repeating the question, but he's not heard.
(at around 2h 40 mins) When Rose and Jack are on the ship as it is going down vertically, Jack says "Hold on!" about a second before his lips move.
(at around 56 mins) When Jack approaches the door to the grand staircase for the first time, the camera is reflected in the glass.
(at around 1h 26 mins) The hands sketching Rose are clearly too old to belong to Jack. (They actually belong to director James Cameron).
(at around 1h 40 mins) Just after the collision, as Captain Smith walks to the starboard bridge-wing to look over the side to inspect the damage, the camera's shadow is visible in the bottom-left corner.
(at around 1h 21 mins) When Rose is stepping onto the railing during the "I'm Flying" sequence, in the widescreen version of the film we can see to the very right that the railing is ending and there is a cable visible dangling over where the railing ends.
(at around 13 mins) The skids of the camera helicopter are reflected in the window of the helicopter taking Rose and her granddaughter out to the Keldysh.
(at around 54 mins) When Jack and Rose are spitting over the deck before dinner, they are on the port side of the ship, and the sun is setting almost directly in front of them. The ship would have to be going northwest for this to happen instead of the southwest course it should be on.
(at around 48 mins) While walking on the deck the day after Jack rescues Rose, just before she shows him her ring, if we look over the ship's rail, we can see waves coming into shore.
(at around 21 mins) A strip of desert is visible between the dock and the Titanic when it's docked at Southampton.
An overhead shot of the ship on its way to New York shows the shadows of the masts falling to the left, but the sun is shining from the left (=south) also.
At 31:40 Jack is looking over the railing and sees dolphins following along with the ship. The dolphins pictured are Pacific White-Sided Dolphins instead of the Atlantic Bottle-Nosed Dolphins that inhabit the Atlantic Ocean.
Whilst demonstrating how to spit, Jack projects a glob of saliva through the air. During those same few seconds, Rose shuts her eyes. Yet when Jack asks, "You see the range on that thing?", Rose claims she did.
(at around 15 mins) When old Rose is seated in her stateroom aboard the salvage ship with Lizzy her granddaughter and Boudine comes in to ask if her stateroom's all right and if there's anything she'd like. She replies, "Yes, I'd like to see my drawing," and behind her on the wall we can see a large banana shaped shadow of the boom mic dip down for her line and up again.
(at around 1h 11 mins) In the open matte 3D version of the film, Cal tells Rose that she is his wife if not yet practiced by law and that she'll honor him. When he says "so you will," a shadow of the boom mic is visible.
Thomas Andrews is portrayed as having a soft Irish 'brogue' type accent. He came, in fact, from a staunchly Unionist background in Belfast (his brother was the future Prime Minister of Northern Ireland) and he would have had the same upper class British accent, which was a common feature among the wealthy landed gentry of the period and indeed is still common to this day.
Most of the children have American accents, despite their parents having foreign (British, Irish) accents.
(at around 15 mins) At the beginning of the movie, Lizzy questions her grandmother's claim that she is the woman in the drawing, Rose Dewitt Bukater. However, the photographs of Old Rose's life at the end of the movie show her younger and with an uncanny resemblance to the appearance of the woman in the drawing. It seems strange that Lizzy would never have looked at photos of her grandmother's life before, if she did, she would certainly have noticed the similarity. Lizzy even helped her grandmother unpack the pictures in their stateroom when they arrived on the Keldysh, but apparently didn't even notice the similarity then either.
Someone getting into a lifeboat is wearing a digital watch.
(at around 17 mins) When Lewis Bodine is talking about the moment the iceberg hit the Titanic he states that it "punched holes like Morse code... below the water line" in the hull; however, this is not the case. There were many possible factors in the sinking but the closest to Bodine's statement is that when the iceberg hit, it popped the rivets, causing the hull to open and let the water pour in.