New LoRA lets you steer the sun in FLUX.2 Klein with a reference ball
Developer eric-venti-seeds just released Sun-Direction-Lora-Flux2Klein9B on Hugging Face, letting creators pinpoint exact sun angles in outdoor generations using a simple 3D reference sphere. The workflow neutralizes original lighting into an overcast plate before casting sunlight from the chosen direction. Why it matters: precise light control has always been painful in diffusion models, and this brings an intuitive visual gizmo to the process.
Sun-Direction-Lora-Flux2Klein9B is an open-source LoRA built on FLUX.2-klein-9B that solves one of diffusion models' oldest headaches: getting the sun exactly where you want it.
Instead of wrestling with prompt words like golden hour or harsh side lighting, it lets you supply a simple 3D reference ball. Wherever the highlight sits on that ball, that is where the sun will shine relative to the camera angle.
How it works
The secret is a two-step relighting pipeline. Direct sunlight looks messy if the source image already has hard shadows, so the top half of the workflow turns the scene into a flat, overcast plate first.
Once the scene is neutralized, the bottom half casts directional sunlight based on the reference sphere. If your source image is already overcast, you can simply bypass the top step.
Triggering the effect requires the prompt match the sun direction from the reference, after which you can append instructions like add a clear blue sky or keep the cloudy sky.
To generate the reference ball, creator eric-venti-seeds provided a dedicated Sphere Render Node alongside a companion Blender scene. If you want to render sun-dial timelapses across different times of day, fixing the seed prevents flickering between frames.
Specs and limitations
The weights are available on Hugging Face, with setup templates ready for Google Colab and Kaggle. Alongside the primary 9B release, there is also a lighter FLUX.2-klein-4B checkpoint for lower-VRAM setups.
The main catch is domain coverage. It was trained strictly on exterior environments, so interior scenes will fail. You also still have to deal with the intermediate overcast generation.
A v2 is already in the works, aiming to eliminate that overcast step while adding sliders for light hardness, color, and intensity.
Why it matters
3D artists have rotated sun spheres in viewports for decades, but generative AI usually makes users guess text descriptions to adjust shadow angles. Bringing visual relighting widgets into image generation is a massive quality-of-life win.
If you build environment concepts, architectural visuals, or consistent storyboards with FLUX.2, this is well worth slotting into your ComfyUI setup right now.
Sources (1)
- huggingface.co(opens in a new tab)Originalhuggingface.co