Audiophiles have this habit of hearing things from their stereo systems that are not there. I don't personally have any problem with it, but it does lead them to spend a great deal of money. There are two ways, at least, to define not there. The first is does not appear to be measurable. This is routinely countered with "my ears are more sensitive than your instruments" or "you are measuring the wrong thing." The second way is no two people "hear" the same thing. Audiophiles get around that with a combination of meaningless phrases, and talking together. Everyone agrees that "the sound stage is so much more three-dimensional" and "the mid-tones are more vibrant" because in the first place those phrases don't mean anything and in the second place they talk to one another and agree on it.
If you do actual double-blind testing, you find that there's no such thing as most of what audiophiles hear. In these senses of not there at any rate.
This in no way interferes with their enjoyment of their audio systems, and it should not. They love their three dimensional soundstages and vibrant mid-tones. They should, they paid a great deal for them! The key point here is this: if you have a specific perception about a thing, but nobody else shares it, the perception is almost certainly about you and not about the thing.
Onwards to art. Consider again the problem of "art as portrait of the artist". This is really a stand in for a wide variety of fiddle-faddle, we could have the same discussion about really any feature of a piece of art. Sometimes the results would be positive, other times it would be negative.
On the one hand, I have argued that no piece will actually reveal the artist in any meaningful way. On the other hand, who am I to tell the viewer that they do not feel the artist's hand? If you see a photograph, and feel that through it you have grasped something essential about the photographer, well, more power to you.
The question of whether anything is actually communicated about the photographer is still a fair and reasonable one. It's probably ridiculous to attempt to measure the presence of the photographer in the image. I can think of no measuring device which would tell us much on this front.
However, we can force two people who "feel" the photographer to compare notes in a blinded fashion. Perhaps they could write a few lines, without first consulting one another, and then we could quite literally compare their notes. I feel confident that, were this done with due care, the notes would be uncorrelated almost exactly to the extent that the mean something. It's quite possible that that there would be some shared phrases that don't mean anything, repetition of the claim that "I feel the photographer" dressed up in a couple of disguises, and some shared material that boils down to discussing the style of the image. Any actual insights about the photographer: "he was tall", "she was depressed", "he had red hair" would be essentially random.
Guessing the gender of the photographer would be a neat and very specific test.
If people cannot agree about what they perceive about the photographer, then their perceptions are internal and have not much to do with the photograph. The photograph does not in fact reveal the photographer, in any meaningful way. If we were to ask instead about the subject of a photograph of a tree, likely everyone's notes would say "it's a tree" and then we could agree that the photograph does, in a meaningful way, convey the idea of "tree."
To be quite fair, I don't know this for sure. This is pure opinion and speculation on my part. It would be interesting to give it a shot, though!