<< You are making this much too difficult. Dick Sullivan basically had it
correct. The pinhole image is simply the shadow (or anti-shadow rather)
of the pinhole at a continuum of points across the image plane. Each
point in the image plane is simply illuminated by the light that can be
seen through the pinhole at that position.
OK I get it. Imagine a gazzilion straight lines passing through the hole
from the subject to the film. If it's light at one end (subject) it will be
light at the other end (film), and if it's dark at one end it will be dark at
the other. Eureka, an image!
<< Now, has anyone tried building the opposite of a pinhole camera? You
should be able to get an image from the shadow cast by a pin speck. The
physics is the same.
Let me see if I understand. The speck would cast a shadow "at a continuum of
points across the image plane." Meaning that if it was light at the subject
end of the continuum, it would be dark at the film end (because of the
shadow), and if it was dark at the subject end of the continuum, at the film
end it would be..., umm..., wait a second..., don't tell me...
Maybe were are not smoking the same cigarettes.