Visible crew/equipment: In the episode where the doctor tries to save the woman who is drowning, when he enters the water for the second time just as he says "there's someone else out there", you can easily see the keel water of the boat or Jet Ski that is filming him.
Continuity mistake: When Jack hangs off the cliff, he grips a vine covered in a multitude of leaves in the wideshots, but in the three tight close-ups his hand is dramatically shown slipping down a vine, without any leaves on or around it. He also remains at the same height position the entire time.
Continuity mistake: When Jack, Hurley and Charlie discuss water situation, the suitcase filled with water bottles repeatedly changes. One example: when Charlie carries the stuffed suitcase, then sets it down, it is open just a couple of inches, but when Jack walks away the suitcase is bursting with bottles, and is open at least 18-20 inches.