Does the Coordinate system of a data frame in ArcMap have to match the coordinate system of at least one of the layers in the table of contents?
I have found that if defined it will take on the coordinates of the previous layer. If both undefined it will stay undefined? I am not sure if the answer is yes or no. I believe it is yes because I have found this excerpt.
By default a data frame (the map display area) takes on the same coordinate system as that of the first spatial data layer added to it. It is important to realize this. But,assuming that all of the layers in your data frame have their coordinate systems defined properly, you can set the data frame to display your data in any desired coordinate system, regardless of the coordinate system of the layer you bring in first.
To me it is a bit confusing. So if the coordinate systems are all defined then the answer would be no, I assume. Can anyone clarify this for me?