The picture shows the Superdome in hi-resolution - 1.2m/pixel.
This is done with a flatten under the textures since New Orleans is quite flat nothing is really changed from the air. A problem with these textures is that distant textures may not be "in-focus" until you are over them. Then those that you have left loose focus. There may be a relevant range parameter somewhere for this. In worse case very distant hi-res textures turn green until you approach them.
Dick Boley near 5G8