Hi walk-hour,
Please note that I write in a forum, and whatever I write is not an evaluation of your work but more an attempt to share as much as needed to get even a beginner started.
Preamble:
What is it that you try to achieve? Yes, you say Photorealism, but is it Realism, Hyperrealism, or Photorealism? Photorealism is quite a wide field, and I believe you will get many different answers to that idea.
Lenses are often the most crucial part of the Photorealistic quality. Since film time, the digital way of defining this has changed, and lenses with clear artifacts are commonly seen as more able to provide photorealistic ideals, as they leave a specific "feeling" in the image, mostly the opposite of being clinical.
. Lenses are typically a compromise, except for a few - often quite expensive ones; the great exception is Sigma's Art 40mm F/1.4, which leaves nearly no signs of any influence other than being nearly
perfect. I mention that as the term has changed over time. However, there are certain ideas about what it is; it depends on who you ask. It is similar to Filmic, which is an endless discussion for many.
What is it?
So, what is the idea when the term photorealistic is used? (Part of my art education at the University of the Arts in Berlin (MFA) was Photography (3 years photography, then 3 years cinematography). Even after decades of shooting, I would not dare to pin that term into a small definition.
Long story short, using photorealistic is not a simple idea; the more one trains one's perception, the less likely one is satisfied with anything.
However – there are several resources to answer that:
The Complete Guide to Photorealism for Visual Effects, Visualization and Games 1st Edition, by Eran Dinur (Author)
He fills a whole book with the idea of Photorealistic, and I enjoyed reading it. Is that all there is to it? No.
Or a tutorial/presentation series:
https://cineversity.maxon.net/en/tutorials/rendering-interiors-and-exteriors-1-4-create-with-maxon
Your image:
Your image would work more towards Hyper-Reaslistic, as no sign of any optic nor filtration is there, and the visualization is very generative (Nothing wrong with that. To boost you with that, explore Ed Ruscha, a celebrated artist in L.A. and beyond.
The 400-pixel height image doesn't allow for many investigations, especially with the artifacts from compression.
How was the edge treatment to catch some light? Hard to tell. There is no sign of color grading. I did not find a light wrap.
Typical elements in Compositing are often missing in a single render result; even compositing is not the theme; the qualities to match an image are, as it is the same as adapting a rendering to an image or working towards a photorealistic.
https://cineversity.maxon.net/en/series/integration1?tutorial=1_integration_introduction_01
I typically avoid the term photorealistic, as you might imagine by now, as it is blurry at best. Leave the lens cap on the lens and get a photorealistic black image.
Reference:
What better reference could you get than from the Masters of Architectural Photography, and here rely on books? Web is not the best idea.
The key is your references, the one you shot, not anything from the web. Then you know what you get. Considering you are savvy with a camera.
If you want to have 3rd-party references, books about architecture are a good study. Typically, the VIP in that genre attracts the best photographers.
The parts you need. To look at why your example looks hyperreal and not as you wanted. Some things rendering engines do not deliver, and why often Compostings are the only way to work.
Here is an older series of mine that explains ten main qualities to merge things into reality:
https://cineversity.maxon.net/en/series/integration1?tutorial=1_integration_introduction_01
Subjective treatments. Again, I have no idea what you have in mind regarding photorealism. This is a quick (a few minutes) Photoshop treatment of your 400-pixel high image from above. Compare it.
I hope the content suggestions allow you to find your aesthetic and create a signature look with your work over time—my best wishes.
All the best
