What color image is formed when using iodine vapor on latent fingerprints?

When using iodine vapor to visualize latent fingerprints, the resulting color of the image typically formed is brown. This occurs because iodine molecules bind to the lipids and oils present in the fingerprint residue. Upon exposure to iodine vapor, the chemical compounds in the fingerprint react and produce a brownish tint.

This method is especially effective on porous surfaces and offers a temporary visual enhancement of the print. It's important to note that the brown coloration is due to the physical properties and the chemical nature of iodine rather than any staining method involving dyes or inks. The transient nature of the image formed by iodine vapor means that it can fade quickly, which is why photographs of the prints are often taken shortly after development for permanent record-keeping or further analysis.

Understanding the characteristics of the colors produced by different development techniques is crucial for forensic examiners, as each method has its own applications and visual outcomes depending on the substrate being examined.