Detection

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The most widely used method of detecting latent prints is to dust using a fine powder that adheres to the traces of oil and sweat.

There any many different kinds of powder in use today for example;

aluminium dust, which is grey and highly visible on dark and mirrored surfaces

carbon black for white surfaces

luminescent powders which fluoresce under ultraviolet light

Dusting is suitable for hard and/or non-absorbent surfaces, for porous surfaces like paper or cloth another approach is needed. Here chemical treatments are used;

	iodine fuming
	ninhydrin
	superglue fuming

For more information on the enhancement of latent fingerprints follow this link;

Enhancing Latent Prints

Once it has been detected the fingerprints needs to be preserved for use in the investigation and later in court. Before this is done the print is photographed at a scale of 1:1. The fingerprint examiner will then compare these crime scene photographs with photographs of suspects fingerprints using a comparison microscope.

[ Up ] [ History of Fingerprints ] [ Basic Principles ] [ Fingerprint Types ] [ Detection ] [ AFIS ]

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