3D Perspective Question

[denzjos]

Some information I know as an amateur photographer. When you take a photo from an object with different lenses (different focus 24mm/35mm/100mm, etc) from the same distance to the object, then the photo is showing more ore less information around the object (same as digital zoom in smartphones). When one do the same (different lenses) but with a different distance, and want the same information on the photo, it result in photos where the distance between the objects is shorter or longer and the objects behind the object become bigger or disappear behind the object. Try it with a pencil in front of your eyes and hold the pencil in different distances, you see more or less information behind the pencil. What I am trying to say is that is nearly impossible to let two photos taken with different viewpoints (distance) fit them together. It is also difficult to blend several handheld photos (= several little different viewpoints), let us say, to a HDR. Programs that solve that problem blend the ghost information together so one think the photos fit but it's improved by some programmed magic. I've included a link that explain this stuff, look at the beginning to the photos with the little blue monsters.     
https://www.studiobinder.com/blog/focal-...explained/