Revealing mistake: In several episodes, but mostly in series 6, we see lots of profile camera shots of just Lister and The Cat at the front of the cockpit in Starbug. Quite a few times you will see Lister mouth The Cat's lines so he knows when to start speaking and what to say.
Revealing mistake: As Lister tries to sharpen/shorten his nails after getting out of deep sleep, you will see just before he stops that one nail snaps at the finger. He continues as if nothing happens, holding his hand still, as if it was still in the sharpener. (00:02:00)
Revealing mistake: Just after we see the first meteorite, there is a brief moment where the model shot and the crew walking into the cockpit overlap causing both images to be seen together. (00:16:55)
Revealing mistake: When Starbug gets hit by the meteorite, the word 'Starbug' on the ship is backwards revealing the film has been mirrored. (00:18:25)
Revealing mistake: The spike that kills Pete Tranter's sister is visible before she reacts to it, just below her elbow. (00:21:20)
Revealing mistake: During the 'Two Listers' scene, specifically the cut when Kryten tosses the apples to the Listers, the split screen is quite visibly moving in between the chairs. (00:22:55)
Revealing mistake: When Legion places the hard light in Rimmer's light bee, it is noticeable that the hard light does not go inside the device. It is placed more to the area beside it. (00:09:55)
Revealing mistake: During the scene in the space station's dining room, when Craig Charles is making a speech explaining that they should escape, he stands up and pours himself a glass of Bucks Fizz. Craig fills the glass too soon (half way through the speach) and must realise, as he pours the drink back into the pitcher, and then begins filling his glass again. (00:20:20)
Revealing mistake: When Lister hits Legion over the head, his mask falls off. In the shot that shows Rimmer, Cat and Kryten in the foreground sitting at the table and Lister and Legion in the background, Legion's face can be seen and it is apparent that it is not the combination of the four that is his face, but in fact the actor's real face. (00:21:15)
Revealing mistake: When Legion gets hit, you can see his real face for a second when he adjusts his mask. (00:21:30)
Gunmen of the Apocalypse - S6-E3
Revealing mistake: When the Cat says 'not if you believe those lying cartoons' you can see Lister mouth the line. (00:09:50)
Gunmen of the Apocalypse - S6-E3
Revealing mistake: When the crew are trying to figure out how to save Kryten before going into the game, the Cat says 'if not, why not?' You can see Lister mouth the line. (00:15:25)
Gunmen of the Apocalypse - S6-E3
Revealing mistake: When Rimmer throws a cowboy over the bar, it wobbles. (00:21:35)
Gunmen of the Apocalypse - S6-E3
Revealing mistake: At the start of the episode, we see Lister in black and white talking to Loretta. Then we cut back to what's really happening, he is playing on the AR console. Look at the door behind him, you can see Kryten's hand sticking out in the doorway. He is supposed to rush in and start talking, but you can see him waiting off camera to be told when to enter the room.
Emohawk - Polymorph II - S6-E4
Revealing mistake: When the Gelfs release the Emohawk, it is thrown into the air and it flies away. However, if you look at the third Gelf you can see the shadow of the Emohawk puppet as it falls to the floor. (00:17:30)
Emohawk - Polymorph II - S6-E4
Revealing mistake: The airlock opens before Ace activates the controls. (00:24:25)
Emohawk - Polymorph II - S6-E4
Revealing mistake: When the grenade explodes, the explosion is to the left of where the grenade landed. (00:26:50)
Emohawk - Polymorph II - S6-E4
Revealing mistake: Both Ace and the Emohawk get sprayed with the liquid Dyllinium, yet only the Emohawk becomes paralysed. (00:26:55)
Suggested correction: Ace is a hologram. Even though he is hard light, he cannot be harmed. Which is why he was able to jump on the grenade and not be harmed. So the gas spray wouldn't have harmed him either.