When I download a drawing like my latest eye study I get some of this, and it's a good question and one that needs to be thought through by every realist.
"Hello, I'm doing some research (not very scientific, I just need some opinions) on photo-realism and I'd like to ask you a question if you don't mind: "why not simply take a photograph or use a 3D program"?
That's a great question and a realist has to answer this for him or herself, If copying without change, construction and re-invention, be it form a photograph or from life, then the creative process is not addressed, in this case I agree there is a useless element about it, it becomes a fundamental exercise at best. There is nothing wrong with these exercises if it improves your knowledge and skills as a technician. But if your aim is only to draw like "a photo", I'm afraid you will never attain what "art" has to offer. Also I think too many photo-realists rely on technical eye candy alone, with no imagination, in some sense just a limited skill in observation and a stunted creative process. Working in this manner should be a foundation to build on not an end goal.
My goal as a realist is to understand complexities and details; my interest is how the human eyes perceive not how a camera sees. The hallmark of photorealism is capturing distortion and out of focus areas precisely how the camera does, I'm aware of these things and eliminate most of them. My journey begins at the first look of my model the drawing process then becomes an all consuming study. When I complete the work, I develop an understanding of the subject that's both heightened and very personal. After spending hundreds of hours drawing a person's face all the while observing the small details that cause "likeness" a journey takes places that cannot be achieved by any other means. I don't draw just what I see; it's a combination of facts and feelings that would not work from just a snap of a shutter. I change and alter many thing from the reference photos to me they are just a blueprint an informal guide at best, I transform not just translate what I am observing. I look at small particulars of a person that cannot be seen or deciphered by "normal" cameras. I delete, enhance, elaborate, exaggerate, alter and reinvent, and I do this with putting it through my own psyche. I change what's in front of me, not for the sake of change but because it's inevitable and expected, it's filtered through 40 plus years of living. I have 100% control of every aspect of the final image can this be done with a photo and Photoshop? Perhaps, but not with my unique and very personal technical and artistic language.
In the end, some still call it photo-realism; it's something as an artist I have to accept. We tend to put things in categories, I just have to keep on this road and be true to my vision and artistic language and it's that honesty that will let me connect with some and not with others.