If you underexpose only highlights are left in the frame as everything else goes to black,
as you overexpose the image begins to go out of focus (optional) and blooms out.

Controls for how much blur and how the midtones and highlights burn out or how much of the original image remains as the exposure is reduced. These will have different effects depending on how bright or dark the original image is, and in some cases will appear not to do anything unless the image is heavily over or under exposed.

Will concatenate if blur is not used.

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