iPhone SDK：将MKMapPoint转换为CGPoint

I have converted a longitude and latitude on my MapView to a MKMapPoint. I then want to move an imageView to that point using the imageViews center property. It seems that I somehow need to convert the MKMapPoint to a CGPoint so that I can change the center, but the numbers seem to be way off. Here is what I am using:I have converted a longitude and latitude on my