The Ansel Adams Fallacy: "True perspective depends only on the camera-to-subject distance"

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I suspected that Adams was well aware of the fact that the perspective seen by the viewer of a photograph also depends on the viewer's position (relative to the image). So ... why didn't he say that in the passage above? I assume he skipped it there only because it's in the book titled The Camera.

In his book titled The Print, I found this passage:

If readers don't look in that book to see what Adams wrote about perspective when viewing an image, it's not his fault. IMO, it's unfair to characterize the passage in The Camera as a fallacy simply because people didn't read further.

Thank you very much for that. I was unaware of that passage in "The Print".

I am pleased that this is clear evidence that Adams understood the importance of the viewer's perspective as well as the camera's perspective. However, it is a pity he did not mention it in the passage I quoted from "The Camera" because many people since have read that passage and assumed that he had included everything that mattered. I suspect that his book "The Print" is much less frequently read today, so most people (like me) have only seen what he said in "The Camera".

If you look at modern online tutorials on the perspective effects of focal length on the image, there are remarkably few that even mention the viewer's perspective and many of them explicitly make statements to the effect that perspective depends only on the camera position. They often make quite a big thing about saying it depends on nothing else. They frequently make a point of saying that the perspective produced by a telephoto lens can be be proved to be the same as the perspective produced by a wide-angle lens because one is just a small crop from the other.

The fact that so many people have taken the passage from "The Camera" so literally justifies calling it a fallacy in my opinion. It was most likely a completely unintentional omission on Adams' part; I am sure he wasn't trying to deliberately mislead his readers. Nevertheless, many readers have been misled by his failure to mention the relevance of the viewer's perspective.

Lest we lose the point here... There is an obvious answer to the silence that greeted the question. Namely that nobody on the thread actually disagreed with the concept that as telephoto compression, being something we experience when we view a 2D image is in itself a consequence of how it is taken combined with how it is viewed.

As I have oft said, it also involves a perceptual element. And the nature of human vision being scientifically demonstrated to be the one place where we do not see pure geometric perspective correctly it obviously follows that there are problems when you try to define what we observe with a human eye directly to the mathematics of image geometry.

I would also caution against the idiocy of standing of a highway trying to take close-up shots of cars. But hey, I'm not a mathematician so I will certainly be proved wrong here... :-)

@bobn2 Yep, slightly different username but same PITA. I'm offski, I was before but came back when this thread was resurrected coz there was something I was thinking of saying but didn't. You know, we were talking about colour, and colour science and you commented later on in the thread that we really need to use a common language with absolute terms so we can understand each other. Or words like that. Which translates into, roughly, for the subject of colour which you define as something that only happens in the human brain we only talk about it in terms of the mathematical model, or how the camera or the computer handles it. For something defined by perception we only discuss how it is handled outside that perception. Then the gem:

Talk about photography... It might be nice. How are most people supposed to respond to that? What on earth has it got to do with general photography , colour, or the differences between... Talk about alienating a large section of your target audience. You cant think of a more simple answer to the OP's question?

I am no mathematician by choice. I am also no fool. There are a lot of people who may wish to come here who are equally not fools but also not mathematicians. But they can't compete if you don't learn to talk in a language they understand instead of insisting we all talk in the language you understand. I also get the point of equivalence, but a favorite topic on a photo forum (about photography) deliberately cancels out the photo from the equation. But maybe I am a fool and have missed the profound significance of this.

Just sayin'

Also just sayin' that some of the theories here indicate strongly that where scientific method is concerned someone can't tell his AFHE. (Elbow-his).

My last post. BTW DPR has dropped off considerably, it's mostly nonsense and garbage. But that may be the current nature of internet forums these days. It's a musky place and smells like someone trumped.

But referring to it as the Ansel Adams Fallacy impugns him rather than the people who failed to read far enough.

It's just the Premature Conclusion By People Who Didn't Read It All Fallacy.

Even though it was completely unintentional, I think he deserves to be impugned far more than the people who failed to read far enough. You seriously think they should have read right through into his next book before they tried to understand what he was saying?

Yes, I seriously think they should have done that before erroneously spreading incomplete ideas about what he knew and wrote. He wrote correctly about the camera's role in perspective in The Camera. He also wrote correctly about the viewer's role in perspective in The Print.

Rather than deserving to be impugned, I think he deserves credit for understanding and writing about what a great many later photographers did/do not understand.

I agree, I should not have said that. I apologise.

Out of curiosity, I wanted to track down the mathematics/ geometrical solution to this question.

This American academics paper explains very simply and clearly the geometrical relationships.

It is a question of simple similar triangles as I wrote above, which lends itself to a graphical solution on the drawing bord.

The viewing distance is 95mm in my example off axis at V

This explains how to make the perspective effect realistic. Now what if we do not want a realistic effect?

How do we solve this real life cube?

I agree that Ansel Adams deserves credit for his massive contribution to photography, both in the photographs he took and in educating other photographers through his books and courses, etc.

However, like all of us, he did occasionally make mistakes. In his book "The Camera" he devotes two pages to discussing "subjective properties of lenses", including "wide-angle perspective" and "telephoto perspective". He emphasises that the "perspective depends only on the camera-to-subject distance" and nowhere is there any mention of the viewer's position relative to the photograph. It would take only a couple of sentences to mention the significance of the viewer's position.

I suspect that if he were here today, he would be appalled at how many photographers are unaware of the significance of the viewer's perspective and would immediately edit his book to include it.

We're just repeating our positions, and we're not likely to come to an agreement about them. Again, mine is that he said the right thing about the camera's role in perspective in a book about cameras and he said the right thing about the viewer's role in perspective in a book about prints. The subject of perspective in general was hardly more than a passing footnote in his famous trilogy. It was clearly not intended to be anything other than that, so having two brief observations about perspective appear in the specific books where they apply doesn't bother me at all. But I suppose he could have combined all three of them into one big volume, which might have encouraged readers to complete their reading instead of stopping short.

Another of my positions is that I never find much credence in what anyone (myself included) imagines a personage from the past would think or do today. Again, our positions might differ there as well.