Revealing mistake: When Kyle, Elizabeth and Robin are in the truck being chased by Mr. Chiang, in all the outside shots of the truck it is very easy to see that all three of them have been replaced by doubles. (00:09:05)
Continuity mistake: When Raven telekinetically reassembles the broken chime bead necklace, it has about nine beads and is rather tight, but before and after that the necklaces feature about 13 or 14 beads and are wide enough to fit around the others' necks.
Rendezvous with Yesterday - S1-E1
Character mistake: When Tony talks to captain of Titanic he states he was born in 1938, but in episode 4 "The Day the Sky Fell In" it is December 1941, he should be 3 years old, but as a young child he is about 12 years old.
Deep Metal - S3-E2
Continuity mistake: Depth Charge fights Rampage on the beach. Throughout the whole episode, Depth Charge has four fingers. But in a shot when DC doubles over in pain to clutch his wounds, he has five fingers.
Heads Of Beef / Klub Katz - S1-E11
Factual error: In "Klub Katz" the captian yells "Iceburg, Iceburg, on the starboard side." But when you see the iceburg and the ship, the iceburg was about to hit the bow of the ship.
Continuity mistake: The six Rangers are standing together as Wolfbane is enlarged by Orbis. Kat and Tanya change places when switching from the wide shot, to a closeup of the Rangers.
Other mistake: When Spike is thrown out of the base by Megatron at the end of the episode, Optimus calls him 'Splik'.
Factual error: In episode 17 there are some scenes showing sick 4400s all around the world. One of them is being carried into an ambulance car in Frankfurt, Germany. The ambulance car's number plate begins with the letters FM meaning Frankfurt am Main. The correct abbreviation for Frankfurt am Main on German number plates is F - not FM.
Other mistake: When Don and Dr Smith are stealing Sesmar's control unit, look closely at the base of the electronic arch - Raddion is hidden from sight but the careful eye will see his golden feet.
Revealing mistake: We can see Ecliptor's zipper from behind - slightly revealing on Saban's part, considering Ecliptor is supposed to be an evil monster henchman of Astromena's.
Plot hole: Didn't Dexter ever notice the giant fire pit in the ant farm?
Suggested correction: This is more of a question than a mistake. (To be fair, I don't think questions were a feature yet back when this was posted.) No, he didn't. He only noticed the fire pit (and the colosseum) when he was inside the ant farm. It most likely just wasn't visible to him from the outside, or it was too small for him to see it.
Plot hole: The alien-possessed Mason steals Captain Lauritzen's fingerprints by pressing his fingertips to the captain's and "heat transferring" the prints. Big problems here: those prints would now be backwards and for the wrong hand. But when the computer later reads the prints, it fails to notice this and passes him through security as "Identity Correct." (00:23:30)
Mainstream - S3-E3
Continuity mistake: When Kitty goes to get a midnight snack, her hair is down. But a few shots later, her hair is up in a ponytail.
Continuity mistake: Just after Sydney gets the book snatched from her by the guy in car, her hands stay near her body and don't move, but in the next shot her hands are thrown out to the side to add a surprised effect.
Factual error: The communication delay for earth-moon communications is around 2.6 seconds. Yet Emma's daughter simply dials a cell phone and is connected to her Mom in space past the moon in less than that. The communication has no time lag. (00:18:45)
Sanctuary for All: Part 1 - S1-E1
Factual error: When Ashley's Desert Eagle is empty, the slide doesn't lock open.
Slave Island - S1-E7
Plot hole: After Storm's attempt to escape the Genoshan prison is thwarted, she ends up in the ocean right at the shoreline of the beach, where she is captured by a Sentinel. Aside from the fact that it makes no sense for a Sentinel to be hiding in the ocean in the event that a mutant tries to escape the prison, there is absolutely no way that a two-story tall robot could hide in the ocean right by the beach, as the water would be way too shallow. You can even see that the water level only goes up to the Sentinel's ankle area when it is standing upright in the ocean. (00:03:15)
Suggested correction: Perception. (1) The Sentinel isn't as close as it appears. If it were close, then she would have been caught in its waves as it emerges. Also, she would be looking only at its chest circle. It's several yards away. (2) She washes ashore. She fell from the sky. She couldn't have fallen from that great height into shallow water without hitting bottom. (3) It's also a two-story tall robot. Its weight would sink it into the sand. So it could have very well been down that deep.
Visible crew/equipment: When Mork and Mindy are walking away from the lake after they first meet, there is a set of 8 lights in two rows of four in the background.
The Agent Of Year Zero - S4-E14
Revealing mistake: During the scene when Mr. Lyle is talking to the General (butcher character), his glove that he wears on his hand is removed to make a point about his thumb having been cut off. In the next shot, we see Mr. Lyle walking around the desk and putting his glove back on, and you can see his thumb folded under his hand as if the actor was trying to hide it and did not realize it could been seen from the camera angle.
Factual error: When Dan goes into the machine for his MRI a light switches on just as his head enters the machine. MRIs have soft muted lights already in the machine (so technician can see the patient via cameras) they want you to rest and be calm to avoid claustrophobia, there are no bright lights. I have had 5 different MRIs in 4 different machines in 2 different states, all were the same. (00:02:00)