Pixian county is accelerating the pace of "urbanization". Urban construction planning is an important work of urban construction. Therefore, an aerial photographer is needed at a high level.

According to the principle of convex lens imaging, when the object distance is more than twice the focal length, the camera is made according to the principle of inverted image minus real image. At this time, the image distance is between 1 and twice the focal length, and the larger the object distance, the smaller the image distance.

Therefore, when a photographer shoots a city from high altitude, the image distance is slightly larger than the focal length.

So choose D.