This is a first version of an interactive pinhole camera model demo. You can change focal length, subject distance, and object height, and see how the projected image changes.
Projected image height
11.9 mm
Magnification
0.007x
Vertical field of view (24mm sensor)
37.8 deg
Model: h' = (f * h) / z, where h' is projected image height, f is focal length, h is object height, and z is distance.