A lens whose design has been optimized for close-up work, with a maximum reproduction ratio of about 1:1.
The ratio of the size of an image of an object to the physical size of the object. It is sometimes known as reproduction ratio.
One million pixels. The unit is commonly used as a unit of the capacity, or resolution, of a sensor in a digital camera.
Data used to describe other data, typically intellectual content information recorded about an image to enhance accessibility.
A tonal value midway between white and black. 50% grey or a value of 128 on an 8-bit scale.
Micro-reciprocal degree; a measure of colour temperature of a light quoted as the reciprocal of the colour temperature multiplied by one million. Colour correction filters commonly have "mired shift" values.
Calibration of the colours displayed by a computer's monitor using a colorimeter. This is an essential part of colour management.
A type of mains-powered flash head that is entirely self contained and consequently easy to use on location.
Strictly, an image consisting only of white, black and numerous greys. Tinted images based on any single hue may also be described as monochrome.
Motorized camera system designed to automate film transport and rewind, and cocking of the shutter.
Modern lenses may incorporate numerous individual glass elements used to enhance image quality. However, each additional element (glass-to-air and air-to-glass interface) reflects a small amount of light and so reduces light intensity and contrast. A transparent coating (or multi-coating) of a metal-oxide reduces this effect, minimises flare and improves contrast.
Exposure determination system commonly found in SLRs based upon separate measurement of brightness in at least five discrete areas of a scene; typically four quarters and a reserved central area.