When Andy and Barney are seen in the squad car in front of the courthouse, they sit several feet apart, Andy next to the driver's door and Barney next to the passenger door. When cameras change to a closeup, Barney is close enough to Andy that their shoulders nearly touch.
When Andy and Opie are in the boat in the opening fishing scenes the boat used in closeups has a very blunt squared off bow. In the long shots the boat has a normal pointed bow.
Opie is supposed to show the state police how to get to the lake but when they get there, the state police motor cycles are leading the way while Opie is in the car behind them.
When Andy and Barney first get back to town from the lake after Barney informs Andy about the manhunt, Barney gets out of the car and stands on the street yelling "Everyone off the street! There's going to be trouble!" However, there is absolutely no one on the town streets except for the two old men playing checkers on the bench. There are no people on the sidewalks and no cars. The town is absolutely empty. However, when Andy and Barney emerge from the courthouse minutes later to meet the incoming motorcade of state police cars, the town is suddenly bustling with life.
Derekson has to swim back to shore, but when they show him in the squad car, his clothes are dry.
At the lake, when the Captain is telling Andy he doesn't know how he became Sheriff, you can see someone walking in the background on the left.
Emma Brand's home is a plain cottage on, at least, the outskirts of town however this changes in the near future without mention of her moving.