PURPOSE 

In the film industry lens abberations like lensflares and streaks indicate complex camera lenses, hence a big production budget.

But since John Knoll's lightfactory the usual digital way is defining a point in the image with a given brightness. From this point the whole effect is created. But that point doesn't represent the whole area, that actually is bright. Especially big bright areas cannot be represented by one point, neither in position nor in shape.

This compositor node works with the emission and glossy renderpass,

using every pixel in the rendered image as sources

to create complex and vivid lens abberations.

A complex nodegroup with efficient calculation lets you define the intensities of the different lens phenomena:

ghosts, streak, iris, star, halo, dust

The last parameter is quality which simply downscales the calculation to a smaller resolution. with lower quality the calculation gets slightly faster and phenomena get blurry.

This product consists of a blendfile with a sample scene, from which you can append the nodesetup into your scene:

The node is meant for VFX work, Motion Design and huge spaceships with lots of bright windows and engines flying through space approaching strange new stars...