Revealing mistake: The muzzles of the the crew's guns are usually empty, but when they need to actually fire them, you can see a black insert sticking out which is the little pyro charge.
Revealing mistake: On Scorpio, the barrel of Avon's gun is bent.
Revealing mistake: BBC costume recycling allows one of the natives on Helotrix to show up wearing one of Tarrant's old 3rd season outfits. Another wears an even older, 1st season costume of Avon's. (00:22:40 - 00:24:25)
Revealing mistake: The Federation Commander reads a report to Servalan, but when the camera angle shifts to a shot taken over his shoulder, you can see that he's "reading" from a colorful plastic board with no printing on it whatsoever. (00:14:20)
Headhunter - S4-E6
Revealing mistake: When Avon pushes a button to call Tarrant, the entire control panel tips upward, revealing that it's not anchored to the console at all. (00:12:50)
Headhunter - S4-E6
Revealing mistake: After its "borrowed" head is blown off and it rampages through the base headless, the android mysteriously gains 10 inches in height and has much longer arms. If they'd just found a shorter actor to wear the headless costume, it might have looked more convincing. (00:44:05)
Revealing mistake: The dead man, shot by the game computer in the orbiter's corridor, is still moving his fingers, and later moves his arm from resting on his chest to flat on the floor. (00:06:05)
Revealing mistake: At the end, when Tarrant is beamed out, Servalan's position shifts considerably, even though she's supposedly standing still. (00:43:45)
Revealing mistake: Avon and Soolin hide from the processing plant guards in an alcove, but Avon's black-booted foot is sticking out in plain sight. Fortunately, the guards don't seem to notice and walk on by anyway. (00:18:00)
Revealing mistake: Scorpio is in stationary orbit over the planet Malodaar - but a shaky special effects matte causes the "stationary" ship to wiggle and wobble severely. (00:00:45)
Revealing mistake: A bad effects matte causes one of the two ships approaching Xenon to partially dissolve along the way. (00:03:55)
Revealing mistake: A shot of Scorpio en route to Betafarl falls victim to a special effects problem. The camera shooting the model was apparently bumped and shaken, so the ship is suddenly wobbling so badly it's a wonder it can keep a straight course. (00:22:20)
Revealing mistake: When Scorpio flies from its launch bay cut in the Xenon cliff face, it's broad daylight (and no, the planet does not have twin suns) - but the ship casts a shadow on the cliff above itself. There's no possible light source from that angle other than studio lights on the ship model. (00:01:20)
Revealing mistake: Scorpio is attacked upon entering Gauda Prime's atmosphere. The ship lurches left: everyone leans left and hangs on. The ship lurches right: everyone leans right and hangs on. The ship rolls over a full 360 degrees: no one leans or hangs on, nor do they fall out of their unbelted flight chairs. And oddly, those same chairs that held fast here tip over with ease later, when Avon escapes with Orac. (00:13:45 - 00:16:15)
Revealing mistake: Avon & Co. are supposedly racing through the woods and cloudy skies of Gauda Prime in a flyer. But the reflections on the vehicle's windscreen never move. (00:38:45)
