Preserving food, less fighting for food, less roaming to hunt and gather. More stable sense of community. More children. Preserving food, less fighting for food, less roaming to hunt and gather. More stable sense of community. More children.
Contrast sensitivity is the ability of an imaging process to produce an image of objects or tissues in the body that have relatively small physical differences or inherent contrast. The contrast that is to be imaged is in the form of some specific physical characteristic.
In reflected UV photography the subject is illuminated directly by UV emitting lamps (radiation sources) or by strong sunlight. A UV transmitting filter is placed on the lens, which allows ultraviolet light to pass and which absorbs or blocks all visible and infrared light. UV filters are made from special colored glass and may be coated or sandwiched with other filter glass to aid in blocking unwanted wavelengths.