Even in today’s brave new world of ultra-sophisticated, high-tech imaging, a significant number of forensic images are still shot in visible light, and that’s why the latest optical filters as well as some tried-and-true classics can be extremely useful in enhancing forensic images and adding to their evidentiary value. Some can reveal faint or unseen details, others can enhance color contrast or highlight specific colors to bring out hidden patterns, and one can even cut through moderate haze and atmospheric perspective to present a clearer view of distant objects. In addition, there are variable color temperature light sources of different degrees of sophistication that can be used to match the color balance of a scene or differentially emphasize certain hues to facilitate forensic analysis. Their ability to deliver a precise visual color balance over a wide range makes them extremely useful while shooting some types of forensic images and videos, and the fact that the RAW or reference image is created at the time of capture without any post-production tweaking minimizes any subsequent legal challenges to their authenticity. Finally, there is new digital filter-emulation software that offers some distinct operational advantages over the widely used scientific version of Adobe Photoshop.

From: Optical Filters and Light Modifiers for Forensic Imaging in the Visible Spectrum by Jason Schneider