Help with HDRI Lighting

I’m trying to learn how to get photo-realistic results for architectural scenes in Blender using cycles. My first few attempts were total disasters. I knew I had both lighting and materials issues, so I tried copying an example I found on poliigon that used one of their HDRIs to hopefully limit the number of things I needed to figure out. This is the original I’m trying to recreate:

My progress so far is below. I wasn’t able to totally match the way that the concrete blocks are dirty, and I’m sure there are other problems as well, but at the moment my focus is on trying to get the lighting to match.

In my render, the sunlight feels too bright and the shadows too dark. This is especially noticeable around the window on the second story as well as on the light shining through the stairs and the shadows surrounding it.

I’m starting to wonder if there is another light source. I tried using both point and area lights above the model, but then it loses the contrast between the shadows on the floor between the front and back. I also played around with a wall immediately behind the camera. This brightens things up, but then it reflects a lot of light and the back of the stairs are much brighter than in the original, so I don’t think that’s right either. I also tried putting in trees using tree billboards, but they always seemed to cast more detailed shadows, so I’m thinking that they’re not really affecting the lighting in the original either. It may also be post-processing, but I’m new to that and not sure where to start.

If anyone had some general suggestions as to how to get the lighting to match better that I could dig into further, I would really appreciate it. Or if someone knows exactly how the poliigon samples were created and would be willing to tell me, that would also be great! :smile:

This is my attempt:

How many light bounces are you using? Maybe increase those to get more light into the shadowed areas.

I don’t see any issues actually. But I don’t really like the idea of being “photo realistic”. There are two reasons for that:

  1. To do that, you’d need access to the original RAW image captured by the camera, and obtain that result from rendering. Then process the image with curves, color correction, and sharpening to obtain photo realism. Better yet, you would need access to lens data to setup correct apertures etc.
  2. Not so much here, but people often want “photo realistic interiors”. And I’m like, "no you don’t, you’re looking for eye realistic interior - how your brain interprets the scene. When they say “I want it to look like this photo”, they don’t show the raw photo off the camera, but the manipulated result, which sometimes include use of artificial lighting to balance out the lighting. The result they often want, is something a photographer can’t obtain without manipulation and/or artificial lighting. I think “photo realism” is greatly misunderstood.

Sure, you’re image doesn’t look identical to the source, but it looks photo real enough for me - in the sense that “some camera and treatment could produce this image” (other than texturing and missing objects issues).

Thank you all for the suggestions and input!

The render time really isn’t bad, and in this case I wanted to use the HDRI to hopefully have exactly the same lighting as in the sample from poliigon. The one I posted used 1024 cycles and completed in something like 40 min on my MBP. I can’t really tell the difference between 1024 and 512 cycles though.

I tried increasing the light bounces. I was originally using the default settings (max is 12) and I changed them all to be 64. I couldn’t tell any difference. I also played a bit with different exposure and strength settings on the HDRI, but I couldn’t get the balance better.

I also think it doesn’t look too bad, but in other renders I’ve done I have also had the same issue where the highlights are too bright and the shadows are too dark compared to whatever my reference was. When I was using a reference photo, I’m sure there was some kind of post processing going on, which is why I chose the reference from poliigon since it’s also a render and was hoping they didn’t do any post processing on it. All of the post processing I have tried just makes things look washed out.

Maybe I need to go study photography for awhile to get a better idea of what the original raw images would look like. I guess I’ll leave this one for now and come back once I get some more experience with a few other scenes.

Thanks again for everyone’s responses!

Yeah I see now that yours is a bit washed out in the highlights, I honestly didn’t catch that before. And I didn’t catch that it was a Polygon example render, I though it was just the HDRI and textures came from them.

I’m assuming you’re on filmic already? Did you try a less contrasty look or play with the CM curve?

Thanks for taking another look!

I am using filmic, and I tried playing with the color management curves, but honestly I don’t really have any idea what I’m doing with it. It’s probably something I need to learn how to use though.

Is color management a good place to start trying to get things to be less washed out (vs trying to change something in the lighting configuration)? If so, that’s very helpful direction and I’ll go learn about that for awhile.