LIGHT OBJECT: Area Light

Area Lights are lights that emit from an object other than a point in space. Unlike point lights and spot lights, where all rays originate from one point, area lights scatter rays from an entire surface.

The preset geometry to use as emitters include a grid, line, disk or sphere, but because this type of light emits so many more rays in all directions it is much more complicated to calculate. This results in slower render times, and since the rays are being scattered from the surface of the light, there is a much greater chance that areas may not be hit with rays accurately. This causes a noisy or grainy look to the renders. To fix this the user can bump up the sampling value in the lights parameters. The default is set to 1. Bumping up this value will make your area light emit more rays which will increase render times, but it will smooth out the noise.

Shading Rate:  01

Shading Rate:  10

Area Lights also give you much softer shadows since the light is able to "wrap" around the object. The larger you make your light--Area Size parameter--the softer your shadows will become.

Small Area Light, Sharper Shadows

Large Area Light, Softer Shadows

Normalize Light Intensity to Area - When this parameter is enabled, the intensity of the light does not change as the user changes the size of the Area Light. When it is disabled, the intensity of the light will scale with the size of the light.

Pros:

• More realistic lighting
• Softer shadows

Cons:

• Longer render times
• Sampling