. In Fig. 3, we show the microscopic images of the fingerprints on a glass slide: (a) and (b) are bright-field images while (c) and (d) are the dark-field images. The fingerprint debris on the glass slide can be discerned in the plain fingerprint marks (b and d), the CTF deposition in (a) and (c) clearly enhances the visibility of the fingerprints. The scattering nature of the CTF appears to make imaging using dark-field techniques which only images the scattered light most suitable for smooth substrates with minimal scattering.