I mean, I can look at a blank wall, and if you say "superimpose a red circle in the middle of the wall" I can very easily imagine that wall with a red circle on it. But I can't "see" it in the sense that you can see the afterimage of the apple on the blank screen. Are you saying you can see in a way indistinguishable from normal vision an imagined object in your field of vision?
I would characterise myself, per your original question, of being able to superimpose imagined objects onto my visual field.
I would not say that such a superimposed red circle is entirely indistinguishable from a real one, but the experience is very much akin to seeing. For one thing maintaining superimposed objects requires a degree of mental focus of which I am constantly aware, especially if the object is detailed and solid.
This feels a bit like "is my red the same as your red?". What do even mean when you say you can "imagine that wall with the red circle on it", but you can't "see" it? Is there no visual aspect to your experience whatsoever? Do you have a spatial sense of the red circle's size and position? Do you experience (hear?) verbal statements about the red circle's existence and properties, or is this some conceptual sense of the red circle that is both non-verbal and non-visual?
The projected image is not typically indistinguishable from normal vision, namely in that there will be an "ephemerality" to the image. Some examples of this ephemerality:
- the projected image usually has a translucency, i.e. it doesn't also block what is behind where it would be physically if it were really there
- the projected image requires sustained concentration and mental effort to maintain detail, and if you let any aspect of your mind wander or stray from the task, the translucency increases, it may pop out of the visual field, or lose details
- the projected image (say, an apple) doesn't have full details at every particular point, i.e. if I focus on where the stem would be, that detail intensifies, but the surrounding areas become more ephemeral; with a real apple, this happens somewhat depending on the focal point too, but not nearly as much
- the projected image can be made less ephemeral and more rich and stable with the use of pscychedelics (e.g. psilocybin) or quasi-psychedelics (e.g. cannabis)
So, yes, you can "see" it in reality, but not, in most cases, to the degree that you "see" a real apple. Often the ephemerality really does manifest in a way extremely similar to how an afterimage persists, but this isn't always the case.