Lens attachment for imparting stray light effects

A method for forming a ghost image comprising:

• defining an image path by aligning at least a first transmissive optic and a second transmissive optic along an optical axis of a prime lens of a camera,
• wherein the first transmissive optic has a first and a second surface and a second transmissive optic has a third and a fourth surface,
• wherein at least two of the first, second, third, and fourth surfaces are curved;
• defining a stray light path by conditioning a pair of surfaces selected from the first, second, third, and fourth surfaces to have an average reflectivity, over the wavelength range between 450 and 650 nm, such that the multiplicative product of average reflectivity percentages for the two paired, conditioned surfaces exceeds 0.0001,
• wherein the stray light path directs light away from and back toward an image plane of the prime lens by reflection between the two paired conditioned surfaces;
• and
• acquiring, at an image sensor disposed at the image plane of the prime lens, an image of an object in the camera field of view and of the stray light.