Confidence and Paranoia - S1-E5
Continuity mistake: When the Cat visits Lister, Lister puts his arm down on the bed, but in the next shot he is leaning on his hand. (00:14:45)

Confidence and Paranoia - S1-E5
Continuity mistake: When Confidence is telling Lister that his song was the greatest love song ever, Lister has his right hand on his lap, but in the next shot, his right hand is suddenly on the guitar strings. (00:19:35)

Confidence and Paranoia - S1-E5
Revealing mistake: In the captain's office, the words 'Medical bay' have been painted on the wall. This was near The End of the episode and can be seen over Rimmer's shoulder while they are talking in the drive room. The set was obviously doubled with the medical bay, as the captain's office is not used in this episode. (00:23:25)
Confidence and Paranoia - S1-E5
Revealing mistake: Rimmer asks Confidence and Lister "Where's Paranoia?", when Confidence replies "I dont know. Is it some place near Uruguay?" Lister is mouthing his lines. (00:24:50)
Confidence and Paranoia - S1-E5
Continuity mistake: When Lister and Confidence go outside the ship, they do a little dance and both put their right feet forwards. In the next shot, their left feet are forward as they continue the dance. (00:25:30)
Confidence and Paranoia - S1-E5
Revealing mistake: When Confidence is trying to get Lister to take his helmet off, Lister climbs over a railing and jumps around him. It is clear that the footage of Lister jumping around was slowed down to make his movement appear as if there is a lack of gravity. (00:26:35)

Confidence and Paranoia - S1-E5
Continuity mistake: When confidence explodes outside the ship, a helmet appears on the walkway which was not there earlier in the scene. (00:26:50)
Revealing mistake: When Lister goes into Rimmer's new room, there is a slight glitch with the split screen. When Lister is laughing at Rimmer's newspaper headlines on the door, the camera changes and the first frame only has Lister and Rimmer with the scutters. In the next frame the second Rimmer appears and the scutter on the right has moved. (00:06:10)

Continuity mistake: When Lister tips his socks onto the floor, he throws the bin behind him, near the bunkbeds. But when he picks them up again, the bin has moved over in front and to the right of him. (00:08:20)
Continuity mistake: When we see Rimmer's Death video, the atomic blast pushes him into the Captain's office. However, in "The End," Holly indicates that the two piles of dust next to each other in the centre of the drive room are Captain Hollister and Rimmer. (00:10:00)
Revealing mistake: When the two Rimmers are exercising, there are no stars visible out of their window. (00:11:20)
Other mistake: When Lister reads Rimmer's diary, he reads the first entry, then his aunt's birthday in July and then the entry for Gazpacho Soup Day in November. Each time he looks for the next entry he flicks though the pages, yet every time he reads, it is from the start of the diary. (00:15:25)
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