Non-Porous Enhancement
Blood Enhancement on friction ridge impressions |
|
If there are remnants of blood in fingerprint impressions, the following chemicals can be used to enhance the blood and make latent prints visible to the naked eye: amido black, acid yellow, leucocrystal violet, and Hungarian red. These chemicals will adhere to blood-specific components such as proteins.
Cyanoacrylate (CA) Fuming |
|
Cyanoacrylate (super glue) fuming is a chemical enhancement technique often used for the detection of latent fingerprints on non-porous surfaces or semi-porous surfaces such as glass and plastic. Once the print is visible, you can enhance it by using dyes or powders.
- Dyes – Chemical reagents used to enhance latent prints. Examples of enhancing dyes include rhodamine 6G, Basic Yellow 40/brilliant yellow, and Ardrox.
- Powders – Chemical reagents used to enhance latent prints. Powders used adhere to the cyanoacrylate and many will fluoresce under specific light.
Gentian Violet
|
|
A chemical used for tape enhancement of latent impressions developed on the adhesive side of tape. The enhanced prints do not need to be viewed under ALS to be visible as they appear bluish-purple to the naked eye.
Sticky Side Powder
|
|
Powder used for tape enhancement for latent fingerprints deposited on the adhesive side of tape. The resulting colour of the friction ridges after enhancement will be black and visible to the naked eye.
Tape Glo
|
|
A chemical used for tape enhancement for latent fingerprints deposited on the adhesive side of tape. The enhanced fingerprints must be viewed under ALS to be visible.
Tape Enhancement
|
|
Any fingerprint impression deposited on the non-adhesive or adhesive side of tape can be enhanced using various techniques
Vacuum Metal Deposition (VMD)
|
|
A machine and associated process in which a substrate with fingerprints on it is coated with a thin layer of gold on the entire surface and only the regions without residue deposits are coated with a thin layer of zinc. This results in a black colouration of the friction ridges. Other multi-metal combinations and the use of silver as the coating metal are new emerging techniques in VMD.
Describes the transfer of oils or lipids from a finger onto a surface resulting in the replication of the friction ridge pattern seen on the fingertip, including the minutiae.
A chemical technique used to enhance an impression in order to increase contrast between the deposited fingerprint and its substrate.
The surface of a substrate that prevents the absorption of a material into the substrate, causing materials to mainly deposit on top of the surface and adhere through adsorption (e.g., plastic, metal, some tapes).
A surface of a material that has some properties of both non-porous surfaces and porous surfaces (e.g., some plastics, some tapes, glossy paper, etc.). Enhancement techniques specific to both porous or non-porous items may work on items that are semi-porous. They have varying degrees and combinations of absorption or adsorption of fingerprint impressions.
Any fingerprint impression deposited on the non-adhesive or adhesive side of tape can be enhanced using various techniques.
Marks or indentations left at a crime scene often in the form of handprints, footprints, or fingerprints that are not visible to the naked eye without some form of enhancement.
Light sources used during crime scene investigations that can enhance the visualization of many forms of evidence, such as fingerprints, to assist with identification. An example of a commonly used ALS is a black light (ultraviolet) flashlight.
The material upon which a fingerprint impression is deposited through contact. Substrates are often classified as porous, non-porous, or semi-porous.
A raised texture on the palmar and plantar surfaces of primates that enhances their ability to grip objects.
