Cameras and Lenses
Nick Marsh · 2014
Forensic photography is based around constructive thought processes, problem solving and occasionally inspiration, not the specific camera we hold in our hand. To have a true understanding of forensic photography one must have an understanding of how our equipment works, whether it is the camera, lenses or processing software. For many years, cameras came in all shapes and sizes but the one consistency was that they all used standard size films. According to the OED exposure is the quantity of light reaching a photographic film, as determined by shutter speed and lens aperture. Three distinct functions: ISOs, apertures and shutter speeds, which are often referred to as the exposure triangle, are discussed in detail. Correct exposure can be measured in a number of ways, either in the camera or through external devices. Most cameras have the ability to operate in three main exposure modes, manual, aperture priority and shutter priority.