Revealing mistake: In the scene in the coffee house, Phoebe is talking to Monica who is drinking a cup of coffee. Towards the end of the scene, the camera is on Phoebe who is smiling & laughing at Monica. In the right hand corner is a side view of 'Monica' however, it is not Courtney Cox in the scene, but a completely different actress. [Widescreen version only, although the "wrong" nose is visible in the original]. (00:06:20)
Revealing mistake: About 1/3 through the episode, they are in Roz's apartment. If you watch when people enter or leave the apartment, the door has a handle lockset. It also has a lock cylinder about 1 1/2 feet above it on both sides of the door. The problem is, the side of the door has no drill hole where the latch assembly should be: it's just solid wood. The lock isn't attached to anything that would enable it to work.
Revealing mistake: Jack Albertson's character is taking pictures of The Cartwrights and ranch hands. The video camera moves across the front of the prop camera as Albertson pushes and holds the button to take a picture. The shutter on the camera never opens and isn't open until he releases the button. In those days the shutter had to stay open an elongated time to enable the light to infiltrate the negative. People had to stay still during this time.
Revealing mistake: When Carrie bumps into Mr. Big and her purse falls, watch the people in the background carefully. Many of them are watching the couple talk and interact with each other. On a busy New York street nobody is going to pay attention to two people having a conversation. Apparently all these people were watching the shooting of the scene.
Revealing mistake: The phone message that Ryan leaves on Luke's voicemail is different to what he originally said, which is "I want to make sure you took care of it. Take care of it," but the message recorded is, "I'm just calling to make sure you took care of it. Take care of it." Also the background sounds from the club - the music, people talking, etc, are missing.
Revealing mistake: At the mill, when John tells Buck that Willie Brimmer might be at the Montgomery cabin with Jim-Bob, in the next closeup of John we see a billowy trail of smoke at the bottom right corner of the screen, but the only people standing there are Elizabeth, John, and Buck, and none are smoking. Presumably, it was someone offscreen smoking too close to the camera (similar to a mistake in 1978's "Halloween"). (00:26:05)
Revealing mistake: When Dylan and Tyr head to a bridge where supposedly the power source is located as well as Rommie, they start to cross the bridge. As the camera is facing Dylan and Tyr, the next scene two aliens teleport in. Rewind the video to facing Dylan and Tyr and play in slow motion. Watch the bottom portion of the screen and notice the top portion of one of the alien's head go into the camera as if the aliens walked into position for the teleportation.