Continuity mistake: When the crew are in the cockpit when Ace Rimmer is entering their dimension, Rimmer hopes that it is not him. When he says this, there is smoke around him, but this smoke was not there in the previous shot. (00:10:45)
Continuity mistake: At the start of the scene where the crew are giving Rimmer a funeral, Lister is shown clutching his "tie", and turns to Kryten, but in the next shot, he is suddenly looking up at the ceiling. (00:24:25)
Continuity mistake: When the crew meet the alternate dimension crew, both crews are standing side by side, but when the two Listers shake each other's hands, the Cat and Kryten from both crews have disappeared.
Continuity mistake: In the Aigburth Arms, when Frank hands the box with baby Lister to the barmaid, the barmaid takes the box placing her hand on top of the box, but in the next shot, her hand is suddenly on the side of the box.
Continuity mistake: When hologram Lister has finished explaining to the crew why he is dead, the crew are standing side by side, but when Lister asks what happened to Kochanski, Cat and Kryten have vanished.
Continuity mistake: When Lister is watching the video message of a psiren, posing as Kochanski, Lister asks "How? I don't understand" and Kochanski, on the video appears to move her face beginning to reply, but when the shot cuts back to the video, Kochanski's face is suddenly still. (00:16:20)
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)
Continuity mistake: When Lister finishes pouring a glass of Bucks Fizz, he begins to place the jug back on the table with his hand still on it, but in the next shot, the jug is now on the table with Lister's hand nowhere near it. (00:20:20)
Continuity mistake: When Rimmer suggests bringing Legion with him, Lister says he's not going to come with them, and asks if he would ever join in on their late night sessions of pin the pointy stick on the weather girl. At The End of the line, Lister is looking to the right, but in the next shot, he is suddenly looking downwards. (00:12:35)
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)
Continuity mistake: When Legion puts his mask back on, just as he says "Kryten knows", the mask is not properly fixed on, leaving his chin exposed, but when the camera is on him next, the mask is suddenly fixed into place. (00:21:35)
Gunmen of the Apocalypse - S6-E3
Continuity mistake: When Lister tells Rimmer that the escape pod is not an option, Lister is looking at Rimmer, but in the next shot, he is looking down at Kryten. (00:12:20)
Continuity mistake: When Lister is explaining the ending of the movie, he says "It's about a dude who sacrifices his life for love" whilst Rimmer looks at him, but in the next shot, Rimmer is suddenly looking forwards before turning back to Lister saying "as if." (00:02:55)
Continuity mistake: When Kryten tells Rimmer he doesn't have the brain that can accept an implant, he says "No" and begins walking around the table. Kryten has his hands raised with his right hand slightly lower than the left, but in the next shot, both hands are suddenly level with each other. (00:22:05)
Terrorform - S5-E3
Continuity mistake: When Kryten cuts off his hand, all of the fingers on the hand are straight and level with each other, but when he goes to attach his eye to one of the fingers, the middle finger is suddenly raised. (00:02:35)
Continuity mistake: When Starbug bursts out of Red Dwarf, the shot from behind shows Starbug spinning in circles, but the shot from in front shows Starbug flying normally. (00:04:00)
Quarantine - S5-E4
Audio problem: When Rimmer is talking to Lister, Cat and Kryten in the dress, the Cat says "We thought you'd gone nuts" and the shot cuts to Rimmer where the Cat then says "We were trying to heal you." When the shot is on Rimmer, the Cat's reflection can be seen in the mirror and his mouth doesn't move with the line. (00:21:05)
Revealing mistake: With the Matter Paddle, Kryten transports into the sleeping quarters, and then transports onto the bunk. When Kryten transports onto the bunk, the Cat's position on his chair visibly alters on screen, showing where the scene was edited to make Kryten appear as if he transporting. (00:03:15)
Revealing mistake: When Kryten transports the Matter Paddle back to Red Dwarf, the position of Kryten's hand visibly alters on screen, revealing where the scene was edited to make the paddle appear as if it had transported. (00:06:30)
Continuity mistake: When Camille asks Kryten if they could make it, Kryten puts his glass down on the table. In the next shot, it is suddenly back in his hand, being put back down again. (00:22:35)
Answer: The cello is a large four-stringed instrument, which, when it is played, stands vertically on the floor between the player's legs (assuming they are seated). If it is to grow as large as the other instuments mentioned will, it would require a rather unseemly lack of femininity to be able to encompass it with the legs.
Rooster of Doom