A few days ago I was helping on a photoshoot where it was snowing and was thinking how cool it would be to do an Arch Viz render with a snowy scene. I wanted to do something relatively quick so I used a chair model I used for another scene, retextured a book model I had, and used Marvelous Designer to make a blanket and curtain. Total work time including render was around 4 hours. The render came out very noisy even using light portals and bidirectional path tracing at nearly 9k samples. I considered using denoising but the problem then became that the denoised image was incredibly blurry. I decided in the end to use a mix of the 2 so I wasn’t sitting on the project for a week since I wanted this done in 1 day. I took the 2 layers into Photoshop and blended them together until I got something I liked and then using camera raw pulled up the texture slider and sharpening just to give it a little added boost of clarity back. I will likely revisit this project again in the future as part of a larger scene where I will spend a little more time on the sampling problem.
The blanket knitting is actually modeled. I likely could have gotten away with a displacement map or bump/normal combo perhaps, since there is a particle system as well, but I really wanted the added realism of the knitting so I modeled out a repeatable loop and arrayed it in both the X and Y direction and then applied the blanket from Marvelous Designer as a deformer for the now knitted blanket so it would take on the shape of the fabric.
The lighting wasn’t behaving from the HDRI how I wanted it to because of a bunch of street lights in the way so I added some nodes to filter out the yellow light and made the film transparent so it would only emit blue light into the scene. I also added a low intensity sun lamp which was also emitting blue which I could make directional and gave it the same light angle as the moons reflection angle which yielded good results. I then comped the new background in afterwards in Photoshop.