1. A method of performing a biometric measurement on an individual, the method comprising: illuminating a purported skin site of the individual placed disposed relative to a platen under a plurality of distinct optical conditions during a single illumination session, at least one of the plurality of distinct optical conditions including illuminating the purported skin site with light at an angle greater than a critical angle defined by an interface of the platen with an external environment and another of the distinct optical conditions including illuminating the purported skin site with light at an angle less than the critical angle; and receiving light scattered from the purported skin site separately for each of multiple of the plurality of distinct optical conditions to derive a multispectral image of the purported skin site.