Continuity mistake: When Dana gives her shopping bags to Frank the doorman, the lettuce is either hidden or coming out depending on the shot, and a long brown bag appears and disappears depending on the angle focusing. (00:01:10)
Continuity mistake: Dana chases the pram and a biker falls seconds before. She passes next to him and meters ahead, she falls on the curb with no one around. In the close-up, the bicycle has appeared next to her. (00:02:00)
Continuity mistake: Egon is running his test on the married couple. He is about to write a note once his assistant has further tortured them with the announcement of another half an hour of wait. Sigourney Weaver has her arms crossed in one shot, but addresses Egon in the next shot having her hand on her chin. (00:06:15)
Continuity mistake: In front of the puppy testing box, Egon tells Dana not to worry and lowers his instrument. Dana gives him her number in the next shot, which begins with Egon holding the device higher again. (00:07:15)
Continuity mistake: During Peter's chat show, the second guest narrates a bizarre and kinda creepy story about the alien who dragged her to his room. She concludes the story with a disturbed expression on her face, but when the camera angle changes and Peter stands, she's actually smiling without any relation to the mood of the previous shot. It is in fact a direct continuation of the very first shot of the show. (00:10:20)
Continuity mistake: In the first scene at the museum, Dr. Janosz Poha approaches Dana that is restoring a Bonington. In this first wide shot Dana is brushing a spot with barely any brown paint on it, but in the close-up that follows she's retouching a different part where the color is thick, and the left side of the painting looks different again when he touches her hair. (00:12:20)
Continuity mistake: Ray answers the phone getting a momentary break from Peter's questioning. He picks up the receiver holding a pencil between index and middle finger, but when the camera angle changes the pencil is gone, and he later picks it from the book on the desk. (00:14:35)
Character mistake: Ray and Egon are giving Oscar the check-up; Ray suggests to run a "Gammill and Pross Infant Acuity Test", which does not exist and is an inside-joke in the screenplay, since Tom Gammill and Max Pross are a duo of comedy writers. Egon agrees and says that they'll finish with an Apgar score, which is a real pediatric term - but it's a test for literal newborns, not an eight months old one like Oscar. (00:16:05)
Continuity mistake: When the doctors are testing the baby, the stethoscope to his right disappears on the back shots. (00:16:50)
Continuity mistake: During Oscar's physical, Ray is holding the recorder in his right hand, then as the camera switches to the reverse angle his tape recorder is in the left hand. (00:16:50)
Continuity mistake: Peter got carried away playing with the kid, and his pitchy garbling summons Dana from the baby bedroom. He notices her and says something about a clear liquid; the tie of the baby bib is fully behind his back, but at the next cut the tie is across the shoulder. (00:19:10)
Continuity mistake: When Janusz is knocked off the ladders while painting Vigo's eye and Vigo comes to life in the painting, the brush he was using is in different positions on the floor depending on the shot. (00:22:30 - 00:23:05)
Continuity mistake: Janusz is knocked off the ladder by Vigo's power surge. He then writhes on the floor as Vigo addresses him, alternatively touching the floor with his hand or not between shots. (00:22:30)
Continuity mistake: At the beginning of the scene with Ghostbusters dressed as construction workers lowering Ray in the dig, Egon's left arm (the one operating the device) changes position between shots. (00:23:35)
Other mistake: Ray obtained a small sample of slime through a very little device, a sphere smaller than his fist. The slime is brought back up in court as "exhibit F" and it is said to come directly from the trunk of their car; the sample is almost 1400 ml, way larger than it should be. (00:25:20 - 00:29:05)
Continuity mistake: The boys upstairs hear Ray screaming to pull him back up from the hole in the ground. Venkman is leaning against it with his left hand, which turns into the right hand at the first cut. (00:25:30)
Revealing mistake: When Ray kicks and breaks the pipe in the underground, the prop was obviously put together to break at the flimsiest touch; it's not just a corroded or even cracked pipe, the two parts are not even of the same color, they were never a single piece to begin with. (00:25:40)
Continuity mistake: Before the trial, Tully leans over the table and tells the boys that he got his law degree at night school; Ray in the reverse shot is holding his pencil at table level, while it was well under it out of frame in the previous. (00:28:00)
Continuity mistake: During the trial, the coffee pot swaps the side it's facing between the front and back shots. (00:28:55)
Continuity mistake: The prosecutor interrupts Tully being fed every line saying that he's "leading the witness." She leans on the table, but before the cut ("Mr Tully...") you see her pull back and begin to raise her hands. Next shot and she is still palms flat on the table. (00:30:25)
Answer: Because she knew Peter would want to get involved. They didn't part on good terms and she hadn't spoken to him since her marriage. She just thought it would be awkward to see him again.
Bishop73