Continuity mistake: As Walt is talking to Saul in his classroom, there is a pen under the desk by the chair leg Walt is standing by. It is next to the chair's front left leg. A few moments later without being hit, the pin moves to the front right leg.
Green Light - S3-E4
Continuity mistake: When Jr says about it being 3 days since the last donation, Skyler is reading a page of the paper that is all columns of text. When the shot changes, there are now pictures on the page and fewer columns of text. (00:37:10)
Revealing mistake: At the end of the episode when Tuco shows up at Walter's house in the backseat of Jesse's car, he tells Walter to get in. As they drive off, the shot pans out to show the street sign across from Walter's house. The sign says Piermont, which is the real name of the street. In the show, the Whites live on Negra Arroyo Lane. (00:48:00)
Visible crew/equipment: At the very end of the episode, right after he tells Jesse how he used the red phosphorus to kill the gunmen, Walt leans down to vomit. You can see his microphone transmitter under his shirt. (00:54:20)
Visible crew/equipment: When Skyler is rubbing oil on her stomach and preparing herself in the bathroom, a camera and cameraman's hand is visible for about a second from the left side of the mirror. (00:10:30)
Box Cutter - S4-E1
Revealing mistake: In the scene where Hank is on his laptop bidding on a mineral on 'Mineral Emporium', the address bar shows 'C://.' which means the web-page is in his own documents on his laptop. No way he can bid on a mineral if it's not online! (00:24:15)
Dead Freight - S5-E5
Plot hole: Preparing to steal methylamine from the train, Walt, Jesse and Mike measure off a predetermined distance from the railroad crossing, which happens to coincide with a handy arroyo, where they bury their tanks. Problem is that they couldn't have known that distance (calculated by knowing the position of the methylamine tanker car in the train) until Lydia told them. But she didn't call that info in until the night after they'd already buried the tanks.
Suggested correction: They were counting on the tankers being at the back of the train, far enough away and at a curved angle so that the conductors wouldn't see them, and the hoses they were using would have been long enough to reach the tankers on either side of the one they stole from. Their heist hinged on a lot of educated guesses and luck, especially because they would have had to abort if the tanker was at the front of the train, but being lucky doesn't make it a plot hole.
I'd have to respectfully disagree. When they paced off the distance to the trestle over the arroyo, they had a particular number in mind (814). It's not explained whether this number represented knowledge of how far back the tank car would be if the engine stopped at the crossing. But if it did, how could they have known that? Not even Lydia knew until much later. And why would they assume the tank car would be toward the back of the train? Lydia doesn't mention that. When she calls Walt, all she says is, "I've got it." And even if she were to tell him, at that point everything's in place for the heist to happen at the location where the tank are buried.
IIRC the crew contacted an expert on hazardous materials shipping for advice on the scene. Rail guidelines require tankers containing hazardous materials are at a minimum "six-deep", that is, six cars away from the engine. Lydia probably told them in advance how long the train would be in terms of cars, so they had a rough guideline for which three or four tankers could possibly contain the methylamine. From there, it seems like their hoses were long enough to get to any of the other cars.
The 814 feet was to ensure that the spot they chose would be far enough away from the conductors so as to not be seen. And they weren't assuming the tankers would be at the back, they were just hoping they would be. As I mentioned, if the tankers were at the front, they wouldn't have been able to move forward with the mission. Lydia told them they would only have 6 hours to prepare for the heist after she told them where the tanker would be. That wouldn't have been enough time for them to get an excavator out there and dig the holes for their own tanks to transfer the methylamine into, so they had to guess the best spot to do it ahead of time and hope that's where it would end up being.
Ozymandias - S5-E14
Visible crew/equipment: Skyler pulls up in her car at the home, talking to Walter Jr. about the truck in the driveway. During this scene the camera comes down to her side of the car. Its reflection is visible in the glass of the driver's side window. (00:32:50)
Factual error: When going over the logistics of the plan to kill the ten men in prison, Jack tells Walt that killing Osama Bin Laden was less complicated. Breaking Bad takes place over a period of two years, beginning with Walt's birthday in 2008, and ending on his birthday in 2010. Bin Laden wasn't killed until May of 2011. (00:15:23)
Character mistake: When Hank is brought to the hospital with gunshot wounds, the ambulance and its two EMTs are met outside by two doctors. One doctor says "Let's get him two grams of oxygen. What's his hemoglobin?" This episode's technical adviser was perhaps away for this scene. How much exactly is two grams of oxygen? Orders for administering oxygen would be given in liters, such as two liters per minute (LPM). The line is presumably meant to be 'two liters of oxygen'. (00:02:25)
Factual error: In the opening scene for the episode, a character commits suicide by electrocuting themselves with a defibrillator. The device used was an AED (automated external defibrillator) which analyses the electrical rhythm of the heart and only delivers a shock when the heart rhythm is ventricular tachycardia or ventricular fibrillation. In this case, the device would not have delivered a shock as the person did not have both ECG electrodes attached and therefore would not have detected a cardiac rhythm. The person would also have had a normal heart rhythm.
Green Light - S3-E4
Continuity mistake: In the scene where Walt is talking to Jesse in Jesse's car, when Jesse pulls out the bag of meth it is in a slide to seal bag. The bag changes between this and a regular ziploc bag from shot to shot. (00:19:30)
Visible crew/equipment: Jesse and Mike are driving to the first pickup spot in the desert. The camera pans down over the windmill/pump with the car driving towards us and a classic BB desert scene in the distance. A cameraman is visible in the bottom right of the shot. (00:08:50)
Visible crew/equipment: When Walter walks towards Jesse's house when he hasn't shown up for work a camera and boom microphone shadow is shown on his back. (00:40:10)
Box Cutter - S4-E1
Continuity mistake: When Gus Fring kills Victor and throws him to the ground, a stream of blood runs between Pinkman's and White's legs. When the angle cuts, the stream is now a puddle around Victor's head, no blood near the legs.
Continuity mistake: In the scene where Walter White buys his new car and pulls up the parkway at their house, the wheels are turned when he stops, but in the next close up shot, the wheels are straight forward. (00:02:00)
Box Cutter - S4-E1
Continuity mistake: At the start, there are 2 foam pieces on the floor when Gale opens the box. When he goes to pick them up there are 3. (00:00:30)
Continuity mistake: Mike Ehrmantraut takes Jesse to a house in the desert. He pulls up behind a dark blue car, which vanishes in the next shot, and then reappears.
