2PP: Photo Analysis
Given: A photograph taken in two point perspective.
Construct:
1. Two pairs of lines following parallel edges in the image. Construct their vanishing points. Color code the pairs and their vanishing points by right clicking and changing properties. (Tip: You will need to zoom in and out to do this properly. I suggest placing the lines approximately while zoomed out; then zoom in and adjust your points to make the lines fit the features of the photo more exactly; and then zoom out again to construct the intersections.)
2. Construct the horizon line between your vanishing points.
3. Construct the perpendicular bisector of the bottom edge of the photo. (If the left and right edges of the photo are uncropped, the viewing target is on this vertical.)
4. Mark the viewing target T where the horizon and the vertical midline intersect. Label it T with a contrasting color.
5. Construct the semicircle between your vanishing points. Find its intersection with the vertical midline. Label it U. TU is the viewing distance.
The following image shows the process completed on a different photo than the one you will do.
