Image Definition

Also found in: Acronyms.

Definition, Image


the degree of distinctness in the border between two parts of a photographic image that have received different exposures. In general, the image boundary of an object having a brightness different from that of the surrounding background is always blurred. Depending on exposure conditions, the transition zone from high optical densities to low densities—the boundary region—is between 10 and 50 microns wide for modern photographic materials. A subjective impression of image definition depends on the rate at which the density in this zone changes and on the absolute difference between the densities at the zone’s edges.

Various methods of measuring definition have been proposed that use the maximum or root-mean-square gradient of the change in the optical density in the boundary region. The highest gradient—the best image definition—is achieved only at a certain optimum exposure. Unlike resolution, image definition characterizes the quality of reproduction for relatively coarse details of a photographic image. When the distance to an object is fixed, it is usually necessary to focus the lens in two different ways to obtain pictures with the best definition and resolution.


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Early optics experts discovered that using an aspherical lens in the microscope immediately improved performance by eliminating those spherical aberrations, or the loss of image definition.
Developed using the company's unique Cluster Technology, which involves ink molecules, consolidated into clusters, passing through the piezo print heads without alteration, J -Cube enables supreme printability, fast-drying and high quality image definition.
price of services: 40%; - Technical value of the sample provided by the applicant in relation to its aesthetic and technical quality of the material and its printing quality (accuracy, image definition, good) keeping and delivery of pv reaction to fire: 60%.
With improvements in brightness, color depth, and image definition, Ultra HD is noticeably better than existing technology, on any size screen.
As with much macro photography, cropped-sensor digital SLRs have an advantage in utilising the central area of the lens for better image definition and further extending the working focal length (and therefore the subject to camera distance).
The front camera is 2MP, offering better quality conference calls with the rear boasting a high image definition with an 8MP camera.
MyRay's three-layer sensors feature a thin fiber-optic plate to improve image definition and protect the silicon receptor from direct X-ray exposure.
Additional DBEF (display brilliance enhancement film) dramatically increases brightness, while a low-reflectivity, anti-glare coating ensures deeply saturated colors and crisp image definition whether indoors or lounging at an outdoor cafE[umlaut].
Ricoh's new toner technology, which has smaller, more uniform particles, produces sharp image definition and smooth transitions in gradients.
The three firms are aiming to jointly develop technology by 2011 to reduce power consumption by LCD TVs which is growing along with the increasing size of displays and higher image definition, according to the sources.
Personal videos make a candidate seem like a human being, a point the communications team can work into the narrative before the freak show moment hardens into a image definition.
According to BASF, the nyloflex N 36 resists swelling in aqueous inks and preserves image definition and ink coverage throughout "extremely high print runs.