Visible crew/equipment: When they are at the crime scene, you can plainly see the camera and camera man reflected in Special Agent Lundy's sunglasses several times. When it is a close up shot, it is even more obvious.
Dirty Harry - S4-E5
Visible crew/equipment: After the ambulance taking Deb to the hospital drives away, a crew member ducks down in front of a parked car in the background. (04:36:00)
Visible crew/equipment: When Dexter is searching the empty house, you can see a crew member with his sunglasses on outside the window. (00:45:49)
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)
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.