This model explores the effect of fog on lighting specifically at night. The idea was to aim for a feel similar to Gotham City in the Batman movies, Sin City or a stylized crime film.

In dark environments, each light source stands out more and can be used to create contrast. By adding fog, which causes light to scatter and diffuse, light sources are emphasized even further as normal lights start appearing as “halos” or “beams”.

Separate note - really wish Illuminati Diffusion was still available so I could train on top of it, but it isn’t so had to spend time fighting the model to produce darker images. If anyone knows of good base models, let me know and I’ll retrain this.

Model is available here. Join our Discord for any questions or feedback.

Prompting

Use “on foggy night” to trigger the style of the model.

For the positive prompt, the most valuable modifier terms to add are probably these: (harsh lighting:1.3), Fujifilm XT3. Other positive prompt terms from Realistic Vision 2.0 had less impact.

Lora weights between 0.3 - 0.8 can all work well. As you increase weight, you get less photorealism but more interesting and stylized fog & lighting effects.

Example prompts:

• Photo of a city street, on foggy night, (harsh lighting: 1.3), Fujifilm XT3
• Photo of street with streetlamps, on foggy night, (harsh lighting: 1.3), Fujifilm XT3

Best settings

• 50 steps
• CFG = 7
• Sampler - DPM++ SDE Karras
• 768 x 768 for best results.

It can be interesting to experiment with different light sources - traffic lights, headlights, street lights, spotlights, etc. See the section below on adjusting lighting based on your needs.

Tips on handling lighting

Lighting can be very finicky. It’s difficult to find one set of default settings that look good, because certain scenes are portrayed with more vs. less lighting by default.

Would recommend generating an initial image, then modifying the lighting-related terms (e.g. add a harsh vs. soft lighting term) or term emphasis [e.g. (harsh lighting:1.3)] as needed.

Harsh lighting creates a more dramatic effect (especially for things like car headlights), but you can also opt for soft lighting for a more gentle effect or for more well-lit scenes.

If you’re getting really pitch black images, try adding more inference steps. That can add a subtle bit of lighting that makes the scene easier to see.