🌌 Aurora

Aurora is the effect that drapes a curtain of northern-lights color across your image - those wavy ribbons of green and purple that make a night sky instantly magical. If you're making fantasy landscapes, album art, or any scene with a dark sky and want to add "aurora borealis" without fighting the sampler to draw it, this is a far more reliable shortcut than prompting for it. The sampler will give you an approximation; this node gives you actual light that sits on top of your render.

It's one of the pack's Light Effects, alongside Lens Flare, God Rays, Neon Glow and Holographic. Like the rest, it's a finishing pass for the end of your graph.

How it works

The node generates a procedural aurora as an overlay and composites it over your image. It builds color bands from the palette you pick (each band offset in hue and brightness), waves them with a sine function driven by wave_frequency, then blurs the whole overlay heavily with a Gaussian - that soft blur is what makes ribbons look like glowing atmospheric light instead of neon stripes. It layers in some random noise for organic texture, positions the band on the image via position and height, and blends by opacity.

There's an animation_speed input, and it does use time internally for the shimmer - so on an image you get a subtle live pulse, and on a frame sequence the ribbons genuinely wave.

The inputs that matter

• intensity (0–2, default 0.6) - brightness of the aurora light. This is your master volume.
• color_palette - green_blue (default), purple_pink, blue_cyan, or multicolor. Pick the vibe first; the rest is tuning.
• wave_frequency (0.005–0.1, default 0.02) - how tight the ribbon waves are. Lower = long, smooth curtains; higher = choppy, detailed.
• position (top, bottom, center - default top) and height (0.1–0.8, default 0.4) - where the aurora sits and how tall it is. top + moderate height is the classic look.
• opacity (0.1–1, default 0.7) - blend strength over the source.

Output is the composited IMAGE.

Installing it

Part of ComfyUI-Image-Effects (Orion4D). ComfyUI Manager → search "Image Effects", or:

cd ComfyUI/custom_nodes
git clone https://github.com/orion4d/ComfyUI-Image-Effects
cd ComfyUI-Image-Effects
pip install -r requirements.txt

Restart and grab it under Add Node → Image Effects. No models - just NumPy, OpenCV, Pillow and SciPy.

Gotchas

Standard pack behavior: only the first image of a batch is processed, and it's CPU NumPy (the Gaussian blur on a big overlay is the slow part, but still fine for stills). The real art here is the setup: aurora reads as light only when the background is dark, so this node earns its keep on a dim sky - on a bright daylight scene it just looks like smeared color. Start with green_blue at default settings, then nudge wave_frequency down for a more sweeping, natural curtain.