The Riddler's False Notion (2) - S1-E32
Revealing mistake: The film can Riddler hands Van Jones supposedly contains his silent movie. But the hollow thump, obvious light weight and lack of the distinctive rattle a film reel would make, all reveal that the can is actually empty. (00:19:00)
The Riddler's False Notion (2) - S1-E32
Continuity mistake: When the Riddler has a blindfolded Robin out on the window ledge, the position of Robin's blindfold changes between shots, from covering his nose entirely to being just above it.
Fine Finny Fiends (1) - S1-E33
Visible crew/equipment: When Batman and Robin enter Penguin's hideout at the South Pier, with Penguin and his goons ready and waiting for them, the duo walk to the table and both of their chalk marks (a bit smudged) are visible on the floor where each stands. Then, when Penguin captures Robin and places him against the wall, another two chalk marks are visible on the floor for each actor. (00:20:40 - 00:22:05)
Batman Makes the Scenes (2) - S1-E34
Revealing mistake: While Batman and Robin are being held in Penguin's vacuum room, some of the stunt's dark squibs attached to the balloons become visible during this scene. We can even see a squib spark on the last pink balloon. (00:02:15)
Batman Makes the Scenes (2) - S1-E34
Visible crew/equipment: When Penguin and his fine finny finks return to South Pier with the umbrella filled haul, just as Penguin tosses money at his henchmen, we can see the chalk T-mark on the floor under the table. (00:18:15)
Shoot a Crooked Arrow (1) - S2-E1
Continuity mistake: When the Archer robs Wayne Manor's safe, an unconscious Dick Grayson shifts positions on the floor between takes. At first, he's lying with both hands folded over his chest. A few shots later, his left arm is stretched out over his head. (00:01:30)
Shoot a Crooked Arrow (1) - S2-E1
Revealing mistake: In Commissioner Gordon's office, just as Gordon tells Dale that with Batman and Robin on their side no harm will befall the money, the top of the set is visible at the top right corner of the screen. (00:06:25)
Shoot a Crooked Arrow (1) - S2-E1
Continuity mistake: The arrow Archer fires into the window frame in Commissioner Gordon's office is, depending on the camera shot, angled up, then down, up, down and up again. (00:07:30)
Shoot a Crooked Arrow (1) - S2-E1
Revealing mistake: At Archer's underground hideout, Batman and Robin are strung up by their thumbs, but in fact the stunt wires that lead to their cloaked backs are visible. (00:21:40)
Shoot a Crooked Arrow (1) - S2-E1
Continuity mistake: When Batman and Robin are ensnared by Archer's net, Batman says he will get his batknife to free them. When Archer shoots them down with the arrow, they are apparently unconscious but with no explanation of what knocked them out while stuck in the net.
Walk the Straight and Narrow (2) - S2-E2
Revealing mistake: At the start, while Archer and his goons are riding toward Batman and Robin who are tied to the stakes, when the Dynamic Duo use their Bat-springs the stunt wires lifting them are visible. (00:03:05)
Walk the Straight and Narrow (2) - S2-E2
Revealing mistake: When the armored truck with the ten million is hit, during this scene we can see stunt wires for some of the arrows used by Archer and his goons. (00:09:00)
Walk the Straight and Narrow (2) - S2-E2
Visible crew/equipment: After Archer and his goons have hit the armored truck, when the security guard pulls out the bag of money from the back of the truck and shows it to his partner, the chalk T-mark is visible on the ground between their feet. (00:10:20)
Walk the Straight and Narrow (2) - S2-E2
Visible crew/equipment: At stately Wayne Manor, when Bruce and Dick are practicing their archery, two white tape marks are visible on the grass; one for Dick and the other for Alfred. (00:23:05)
Hot Off the Griddle (1) - S2-E3
Revealing mistake: During the fight in the museum, one of Catwoman's henchmen slams into the wall beside a window. The set wall buckles and caves in, leaving the bottom edge of the window bent and jutting out. A few shots later, though, both wall and window have repaired themselves. (00:14:00)
The Minstrel's Shakedown (1) - S2-E5
Continuity mistake: When Alfred brings the lunch tray down to the Batcave, Batman is holding a soldering iron, working on the electronic bug. When the shot cuts to a close-up, the soldering iron vanishes, and he's holding a clear plastic probe instead. (00:10:15)
The Minstrel's Shakedown (1) - S2-E5
Plot hole: When Batman and Robin explain to the board members at the stock exchange that Minstrel will not be a threat because they dealt with Penguin, Archer, Clock King, King Tut, and Catwoman, in broadcast order, there is a 6-episode difference between Minstrel and Clock King who has never been seen before. To the first-time viewer, they were probably wondering who Clock King is.
Visible crew/equipment: While Batman and Robin are tied to the spit and rotating, when Batman says, "If we could just shake this turn spit pole loose," in the next shot note the shadow of a crew member moving their arm up, at the lower right corner of the screen. (00:03:35)
Visible crew/equipment: When Minstrel and his henchmen race down the stairs, the sound pole rigging shadow is moving at the very top of the screen. (00:04:00)
Continuity mistake: While Batman is telling Octavia that she can go free, his hands are either straight down at his sides or clasped together at chest level, depending on the shot. (00:06:15)
Answer: There wasn't one singular city used. It was shot in and around various locations in California, plus on a lot of sets and backlots. Ex. Some scenes were shot in LA, some in Pasadena, some in Santa Barbara, etc.
TedStixon