Edge & Radial Gradients

The gradient system gives you direct control over how light fades out at the edges of your area lights. Instead of setting up external textures or complex node arrangements, you get simple sliders that generate the gradient automatically. This feature is exclusive to Area Lights and works with all four shapes — Square, Rectangle, Disk, and Ellipse.

Gradients are a powerful tool for making your lighting look more natural and professional. In real-world photography, softboxes and light panels rarely emit perfectly uniform light — the edges are always softer 

than the center. The gradient system recreates this behavior, giving your CG lights the same organic quality.

How It Works

Behind the scenes, the addon generates a 1024 by 1024 pixel 32-bit float bitmap every time you change a gradient slider. Your emission color is baked directly into the gradient pixels, which ensures consistent  brightness whether the gradient is active or not. The bitmap is connected to the emission node through an OctaneRGBImage node using linear gamma, so what you see in the sliders is exactly what you get in the render. You never have to touch a single node — the addon builds and updates everything for you.

Edge Gradient for Square and Rectangle Lights

Square and Rectangle area lights support individual per-edge gradients. Open the light's advanced settings by clicking the gear icon, and you will find the gradient controls directly below the shape settings.  

The All Edges slider adds a uniform gradient to all four edges at once. This is the fastest way to soften the overall light. For more creative control, four individual sliders — Top, Bottom, Left, and Right —  let you set asymmetric gradients. For example, you could fade out the top edge while keeping the bottom sharp, simulating light hitting a surface at a steep angle.

The Hardness slider controls the transition between the lit center and the faded edge. A value of 1.0 creates a sharp hard cutoff — the gradient has a clearly defined edge. A value of 0.0 creates a very soft,  

 wide gradient that fades gradually from center to edge. Values in between give you a smooth range from soft to sharp.

Switching Between Shapes

When you change the shape of an area light, the gradient system automatically adapts. Switching from Square to Disk transitions from the rectangular per-edge gradient to the radial gradient, and switching back  restores the edge controls. Your gradient settings are preserved separately for each shape type.

Practical Tips

For product rendering, start with subtle edge gradients. Set All Edges to a value between 0.2 and 0.4 with Hardness between 0.6 and 0.8. This softens the light panel edges just enough to eliminate the sharp  boundary that gives away a CG light source, while keeping the illumination strong and focused.

For dramatic lighting, use asymmetric gradients. Set the Top edge to a high value while keeping Bottom at 0 to create a natural top-down falloff. This works especially well for lights placed above the subject.  

For disk lights, a Radial Edge of 0.3 to 0.5 with Hardness around 0.5 gives a natural soft-edge look. Push Radial Edge higher for a pronounced spotlight-like falloff, or increase Hardness toward 1.0 for a hard  circular cutoff.

Gradient settings are fully preserved in snapshots, file saves, and setups. Duplicating a light or a layer copies the gradient configuration along with all other properties.