As a photographer, I can see an event or create a scene and capture it. Artists all go through the same process. But to bring it to light, the artists must have the skill to realize the work. The photographer must know how the image will be recorded in the camera, they must know the tones, contrast, color, or gradation of shadows before snapping the image. For black & white, a bit more knowledge is required so that the photographer can perceive in advance how the image will look in shades of grey, or capturing light which is so critical in black & white photography. Go up a skill level and the use of Photoshop or old school film developers allows even more control to bring the vision to reality.
OK, wipe that grin off your face, this is a photography blog. This rant is directed primarily against photographers who believe that just because they have made their images large, that they are somehow better and worth more money. Now, to be fair, these photographers often are not good enough to even realize what makes a great image and are often guided by unscrupulous gallery owners who will take advantage of the artist by getting the work cheap and selling high, convincing its customers that the work is a quality piece that will hold its value for years (as I saw when one famous Hollywood Star bought a crappy wall sized mural for $110k at Art Basel. “there is a sucker born every minute” – P.T. Barnum). But in my experience, if you really talk with the photographer about the image, they know its shortcomings but rather than go out and shoot more, they blow it up and convince themselves it is good.