2. Materials and methods We used 36 transparent foils (approx. 3 x 3 cm, Lexmark Optra CNo. 1402741)(Fig. 1) for fingerprint deposition. First, a foren- sic light source, i.e., side white light, was used to visually scan for finger marks on the surface of transparent foil prior to finger- print deposition. No traces were detected on the examination site. Then, the site was labelled with a number or symbol. Three donors, one male, two female, were chosen from ten participants because of their known ability within our labora- tory to be good fingerprint do Participants deposited fin- gerprints on transparent foil, exerting medium pressure. Their hands were washed prior to finger mark deposition. During the deposition of latent fingerprints the contact time was around 3 s Donors deposited two fingerprints on each transparent foil