Continuity mistake: When Dexter leaves on his boat there are fishing poles behind his seat, but when he turns back around and you see him going away on the boat they have gone.
Let's Give the Boy a Hand - S1-E4
Continuity mistake: A photograph of a landfill is shown from when Dexter is a child, but when Dexter goes to visit the location of the former landfill, an old church can be seen in the background. This church likely predates the landfill as evidenced by its Gothic-style architecture. (00:32:00)
Shrink Wrap - S1-E8
Visible crew/equipment: When Dexter is picking up the fruit dropped by the man carrying groceries, the cameraman is reflected on the side of the car. (00:17:30)
Our Father - S3-E1
Continuity mistake: When Dexter and Vince are next to the dead girl, in the side shot, the tied string from her top is visible on her back and her hair is to the side. But in the overhead shot of her, her hair is covering the tied string and spread more over her back.
Just Let Go - S6-E6
Factual error: When Dexter is looking at Leo Hernandez's criminal history, it shows Leo's social security number. However, it's a 10-digit number instead of a 9-digit number.
Do You Take Dexter Morgan? - S3-E12
Character mistake: The petition for dissolution of marriage was filed on Jan 6, 1990 which is less than 5 months of marriage. However, the duration of the marriage says it's been 6 months.
Dirty Harry - S4-E5
Visible crew/equipment: Before Debra is taken away in the ambulance Dexter is physically stopped from getting closer to the scene, and when Batista tells the cop that Dexter is one of them, in the next shot facing Dexter the reflection of the moving overhead boom mic can be seen on the car window. (00:04:05)
Continuity mistake: Deborah walks out with the yellow shirted man in front of her. Next shot after Quin leaves, the same man re-exits the room. (00:14:00)
Just Let Go - S6-E6
Continuity mistake: When Travis meets his sister at the school she works at, a chalk board with nothing on it can be seen behind Travis. A couple of shots later and there is a piece of paper attached to the chalk board. (00:30:35)
Revealing mistake: When Rita confronts Dexter about his accident being more than minor Rita turns the buggy with the baby in around to leave and it is clear the baby is fake. (00:38:20)
Continuity mistake: When Dexter and Masuka are discussing wanting to go home Dexter throws a can toward the bin and misses, landing by Masuka's chair. In the next shot as Masuka leans down to pick it up it is closer to the bin. (00:39:30)
Our Father - S3-E1
Other mistake: When Debra is talking about her new haircut, she states that she has changed her hair "for the first time since she was 8." However in various flashbacks throughout the show she has drastically different hairstyles from her 'usual'.
Everything Is Illuminated - S5-E6
Continuity mistake: Lumen has a dark "H" shaped scratch on her right shoulder. A few minutes later, its turned 90°, like a sideways "H," and it is very faint. (00:22:05 - 00:32:35)
Revealing mistake: When Deb is texting "Looks like it" to Anton, the buttons she presses on the keypad do not correlate with the message itself and the phone doesn't show any auto-correct feature being utilized, indicating that the text message was added in post production.
Continuity mistake: Episode 3 begins with Dexter at the beach during a funeral. He is wearing a pair of stylish sunglasses. At the start of episode 4, Sgt Doakes is investigating a crime scene at the beach. He is wearing the same pair of sunglasses. Given the tense relationship between the two characters, it is unlikely they would share accessories.
Other mistake: An extra is walking in the background with a measurement wheel while Debra is talking with Lundy outside of the warehouse. The character is hovering the wheel over the ground and not actually using it for its intended purpose. (00:17:10)
Character mistake: In this episode, as well as 1-2 others, Dexter holds his slide phone upside down (only in the edits/cuts where he wasn't shown answering the phone). When the phone is slid open, the front cover goes above/higher than the backside of the phone. And a few instances I've seen, the side closest to his face 'lower' than the outside/backside of the slide phone, strongly suggesting the phone was held upside down.
Continuity mistake: Deb moves in with Dexter to his apartment in a 2nd bedroom during season 2 following the ice killer's kidnapping and attempt on her life. But in Season 5 when they try to share this apartment again, it's only 1 bedroom now?
Do You Take Dexter Morgan? - S3-E12
Other mistake: Debra is checking her email for the traffic cam photo of George King. The sender is labeled "Miami Metro Robbery Div." and the subject is "Photo of George King." However, after opening the email, the send is then a malformed email address of Det.Robertson.Robbery|MiamiMetroPolice.web with a recipient address of Debra.Morgan.Homicide|MiamiMetroPolice.wed (wed, not web), with a subject of "B. O. L. O. Match - George King." (00:26:38)
Other mistake: Lumen agrees to meet her former fiancé Owen at noon. When they meet up, the sun setting in the background indicates that it's evening. (00:16:12 - 00:23:39)
Answer: No, Harry is not the real father. While he did have an affair with Dexter's biological mother (Laura Moser), this was when she was his C.I. Dexter was already born at that point.