It's often the seemingly random details of a particular surface which provide a visual authenticity to a given object. It's that randomness that lets the human mind instantly differentiate between a "natural" object and a manufactured one. A stone made of plastic doesn't quite look the same as a stone made of, well, stone, and our eyes and mind can sort out the faux from the for-real at lightning speed.

And so it is even with structures and textures as familiar to the eye as human skin.

"The human visual system is extremely sensitive to small distortions in skin appearance," says Dr. Sophie Wuerger from the Perception Group at Liverpool University's Institute of Psychology, Health and Society. "Making a convincing synthetic version will be essential whether this technology is used for emergency or cosmetic medicine."

Researchers at the Perception Group are working to develop "synthetic skin" that can be produced with a 3D printer and then matched to a person based on factors like age, gender and ethnicity.

Up to this point, all efforts aimed at reproducing the exact look of skin have fallen well short of the mark, and that's why the team are working to develop 3D image processing and skin modeling techniques capable of rendering a given person's skin so that it appears natural in all viewing conditions.

And that's not as simple as it sounds.

Real human skin is composed of a very complex series of subtle patterns and textures. Moles, discolorations, freckles, scars, veins and wrinkles are spread across the skin like landmarks, and without them, you have a surface which looks more like that on a Barbie doll than that on Aunt Barbara.

Using a 3D scanner can create geometry to exactly match an individual's skin texture and skin tone under varying light sources, and this data can be used to recreate each person's synthetic skin. A custom cover, if you will.

The research team plans to create a 3D image database of skin types captured from hundreds of people to arrive at a "baseline look." It's hoped that 3D printers, relatively cheap at this point, can then access the database of skin types and be used to print out realistic skin.