Surf's Up! Joker's Under! - S3-E10
Visible crew/equipment: After Batman wins the competition, when Hot Dog is finally released from the trash can Joker rushes over to claim it was just a little joke, and the microphone pops up into view at the bottom of the screen. (00:21:10)
Surf's Up! Joker's Under! - S3-E10
Visible crew/equipment: After Batman and Robin head out to Joker's hideout, when it cuts to Joker upon his success at stealing all of Skip's talent and vigor, just as Joker says, "You know what this means boys, the surfing championship," we can see the shadow of the boom mic moving at the far right side of the screen. (00:09:50)
How to Hatch a Dinosaur (2) - S3-E9
Visible crew/equipment: While Batman and Robin are in Commissioner Gordon's office Barbara reports the theft of the Neosaurus egg, and when Batman suspects it's connected to the radium theft, he and Robin decide to use the Batcomputer at the Batcave. Just as the Dynamic Duo rush to Gordon's door the camera turns to follow them, and we can see filming equipment at the right side of the screen as it tries to move out of view. (00:09:55)
How to Hatch a Dinosaur (2) - S3-E9
Visible crew/equipment: After Egghead tells Olga he's planning a three-course meal for the Neosaurus consisting of Batman, Robin, and Batgirl, and for dessert - Commissioner Gordon and Chief O'Hara. Then it cuts to the Batcave as Batman talks about the Bat-geiger, and when the camera moves closer we can see the camera movement's reflection on the windshield, at the bottom right corner of the screen. (00:15:15)
Visible crew/equipment: At the start, Egghead and the Cossacks ride past two women, and they stop to watch, then when the camera zooms in on them the reflection of the moving boom pole/mic is visible on the glass window, at the top right side of the screen.
The Unkindest Tut of All - S3-E6
Deliberate mistake: When Batman has figured out King Tut's plot to steal ancient Egyptian scrolls from the Gotham City Library, he and Robin rush away, and in the shot of the library exterior, the words "The New York Public Library" is quite noticeable above the entryway. (00:18:00)
The Sport of Penguins (1) - S3-E4
Deliberate mistake: After the episode intro, in the first shot we see the words "The New York Public Library" above the entrance to the library, where Barbara Gordon works. However, it's stated in S3xE1 that she works at Gotham City Library, and even in this episode when Penguin listens to the news about the bomb, it's noted as the Gotham Library. (00:02:00)
Continuity mistake: Batgirl's outfit includes boots with kitten heels, but during the fight scenes the stuntwoman's boots have block heels. (00:19:45 - 00:21:25)
Ring Around the Riddler - S3-E2
Continuity mistake: When Batgirl finds Betsy with the huge magnet under the boxing ring Batgirl throws the rope around the lever, then as the rope pulls the lever down the rope slips off and falls, but in the next shot the rope is still up around the lever. (00:21:25)
Revealing mistake: The strings used to operate the bees attacking Robin are visible.
Enter Batgirl, Exit Penguin - S3-E1
Revealing mistake: The panel that Batgirl makes her entrance through can be plainly seen as a prop mounted on top of the set of stairs she comes down.
Surf's Up! Joker's Under! - S3-E10
Revealing mistake: When the Dynamic Duo are locked in the board blanks, you see the jets where the smoke and flame come out.
Surf's Up! Joker's Under! - S3-E10
Audio problem: As Batman and Robin bust through the window, you hear glass breaking, but there's no evidence of glass anywhere.
The Funny Feline Felonies (1) - S3-E16
Factual error: When Batgirl checks Batman's pulse, she states that his pulse is "three beats per minute." However, she only holds Batman's wrist for two seconds. There is no way she could have determined that pulse rate in so short a time. It is unlikely she could have detected even one heartbeat at that rate in two seconds.
The Funny Feline Felonies (1) - S3-E16
Continuity mistake: When Catwoman shoots the bullet into Commissioner Gordon's office, about a quarter-inch of the bullet remains exposed. However, when Batman goes to pull it from the wall, about four times as much of the bullet is now exposed.
Penguin's Clean Sweep - S3-E20
Continuity mistake: After Batman has captured the last fruit fly, he goes to put the vial away in his utility belt. In the close up shot, his hands move toward the left side of the belt. The shot changes to a long view and his hands are now instantly coming up from the right side of his belt.
The Funny Feline Felonies (1) - S3-E16
Other mistake: At the start of the episode, Bruce Wayne and Warden Crichton are overseeing Joker's release from prison, but at the tail end of the last episode, Batman is shocked that Joker is released from jail. He could not be two places at once.
Penguin's Clean Sweep - S3-E20
Revealing mistake: In any of the close up shots of Penguin, his nose has a completely different skin colour than the rest of his face. Making it very obvious that the actor is wearing a fake nose.
Audio problem: When the camera shows the flames of the exhaust, the accompanying sound is wrong. The turbine starting up was played when the flames were seen, instead of the roaring sound effect.
The Joker's Flying Saucer - S3-E24
Plot hole: A time bomb is placed under the dashboard of the Batmobile and goes off inside the batcave. Much of the batcave is ruined, including fallen I-Beams, but the Batmobile has no damage to it even though the bomb was planted in it.
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