A. They have used two different real life towns to portray Iron Lake. And those two towns are 176 miles apart. 

In New Blood, even though Iron Lake was supposed to be in upstate New York, in real life it was actually the town of Shelburne Falls, Massachusetts. In fact the entire series was shot in Massachusetts. ( You can read about it on my New Blood site here.)
 
But for the new series Dexter: Resurrection, filming moved to New York. So they shot most of the Iron Lake scenes in  & around the hamlet of Sparkill, New York, and other parts of Orangetown.  Those scenes included the Seneca Nation Clinic where Dexter woke up from a coma, the Cedar Pines clothing store where he stopped to buy a new set of clothes after leaving Iron Lake, the scenes of Dexter driving away from Iron Lake, and the scene of Angel  & Teddy having a conversation about Dexter while sharing a meal at an Iron Lake diner. All of those scenes were shot in Sparkill, NY.

But when they wanted to include an aerial view of the town, they took a shortcut and simply included an old shot from the New Blood series, Of the original location of Iron Lake, which is Shelburne Falls, Massachusetts. That's the town you're looking at in that aerial view.

The shot is looking southeastern across Shelburne Falls' Iron Bridge, which spans the Deerfield River, and leads to the town's main street, appropriately named Bridge Street.
Here is a StreetView of that same bridge Shelburne Falls: 
 


Here is an aerial photo of the location.  And here is a map link.