The recoverability of fingerprints on paper exposed to elevated temperatures-part 2:natural fluorescence

Previous work by the authors [1] investigated the recoverability of fingerprints on paper that had been exposed to elevated temperatures by comparing various chemical enhancement techniques (ninhydrin, l,8-diazafluoren-9-one, and physical developer). During that study, it became apparent, as a consequence of observations made in operational work [2], that fingerprints on paper subjected to 150 °C fluoresced under examination with green light of wavelength 473 to 548 nm with a 549 nm viewing filter. References