Daytime Downtown Manhattan

I'm trying to accept the whole perspective issue that occurs when I tilt the lens upwards. Can you see how the buildings seem to be converging? I don't have a program to draw the trapezoid that skews the upper section of this photo.

I took this photograph on April 30th, at 9AM. This crane is located in downtown Manhattan, near Cityhall. My eyes were drawn to the oxidized copper rooftop, but I focused the lens on the crane, using a tripod, and my friend's roof.