The first part of the exercise is a demonstration, and the second part is to be completed for a grade. Topography of the terrain is clearly evident upon viewing photos through stereoscope. The large hill south of the lake was thrust up by glacier ice moving from the northeast. The hill is built of material scooped out of the adjacent lake basin. The landscape shows little effect of human development, aside from a road over the hill and several logged strips to the west.
Conifer forest covers the higher areas, and swampy bogs occupy the lower ground.
Find the flying height above terrain for 152 mm lens. See scale formulas. Take care to locate these points as precisely as possible. The distance between principal and conjugate principal points on a single photograph is called photo base . Align the two photos as shown in the handout illustration.