Maybe dumb to suggest, but when this happens usually the lens is dirty / a bit greasy, at least from my experience with iPhone cameras.
> When filmed, the Gaussian Girl is shot through a soft-focus filter, a piece of translucent plastic (or very sheer silk, in the days of classic film), or a quick smear of Vaseline, depending on the director's and/or cinematographer's preference. This surrounds her with a softly glowing aura, and smooths out any unappealing pores or lines on her face. The result makes her look nothing short of ethereal.