One time, when my grandma was in assisted living, I snapped a photo of my sister, her, and me together in her livingroom. While she and my sister chatted, I photoshopped the picture so that we were on a beach in Mexico. I showed it to her, and she was startled and confused – living far inland in the US, even trips to the beach were rare for her, and she had never seen Mayan ruins in person! When I revealed my secret, we all laughed, and she marveled by what a convincing job I had done.
The thing about photography is that it has always (generally) been a two-step process: get an image onto film, then get it from the film onto paper. Amateurs (not in any bad sense) tend to automate those processes whereas enthusiasts tend to take them under their own control. During either stage of those processes, any number of techniques have been used to render images more or less lifelike in all manner of ways: adding tints, reducing contrast, lowering the exposure in part of the picture while increasing it in another part. When these processes are automated – either in the camera or in the development process – someone or something else makes the decisions about how the process is carried out, but those decisions always get made, and in fact, you have never seen a photograph in which there were no exposure- and post-exposure-processing decisions made. They don’t exist.
The question is (1) who makes the decisions; and (2) for what purpose?
(1) When you move into SLR photography, or for that matter, into photography with a point-and-shoot camera that gives a modicum of control over settings, you make those decisions. To some extent, when you select settings like “portrait”, “no flash”, “high quality JPEG output,” you make those decisions. Working in manual mode and with RAW images does not increase the number of options available to the camera/software package, but only increases the number of options that you can directly control.
(2) Fraud is immoral, unethical, and in some contexts, illegal. Fraud differs from mere deception in that it has the point of extracting from the defrauded party something they would not part with otherwise: money, their good opinion, etc.
A mere deception might be, like with my grams, part of a funny joke, or a surprise party.
These things are all clearly different from art, which is intended to show something good, interesting, or beautiful in some way, and not merely to present the thing as a casual passerby sees it. To bring to bear the full range of skill and technical means available to show the good and beautiful in a thing, or to show it in a new way, is hardly novel or particular to photography. It is what artists of all stripes have always done.
Just my two cents.