Which method is commonly used to make latent prints visible?

The method of using graphite powder or talc to make latent prints visible is widely recognized in forensic science. Latent fingerprints are not readily visible to the naked eye because they are composed of oils and sweat left on a surface. By applying a fine powder such as graphite or talc to the surface where the prints are located, the powder adheres to the moisture and other substances present in the fingerprint, making the ridges and patterns stand out against the background. This technique allows forensic experts to clearly visualize and document fingerprints for identification purposes.

The other methods mentioned, while they may have their uses in certain contexts, are not standard techniques for revealing latent prints. Colored inks are not suitable for this purpose, as they could potentially obscure or damage the prints. Digital scanning is more about capturing existing images rather than revealing hidden prints. Photographing under ultraviolet light might help in some instances, but it’s typically used for different types of forensic evidence rather than for enhancing latent fingerprints. Thus, the use of graphite powder or talc is the most effective and commonly practiced method for making latent prints visible.