Image fidelity, often referred to as the ability to discriminate between two images or how closely the

image An image or picture is a visual representation. An image can be Two-dimensional space, two-dimensional, such as a drawing, painting, or photograph, or Three-dimensional space, three-dimensional, such as a carving or sculpture. Images may be di ...

represents the real source distribution. Different from

image quality Image quality can refer to the level of accuracy with which different imaging systems capture, process, store, compress, transmit and display the signals that form an image. Another definition refers to image quality as "the weighted combination of ...

, which is often referred to as the subject preference for one image over another, image fidelity represents to the ability of a process to render an image accurately, without any visible distortion or information loss. The two terms are often used interchangeably, but they are not the same. If we cannot detect the difference between a

photograph A photograph (also known as a photo, or more generically referred to as an ''image'' or ''picture'') is an image created by light falling on a photosensitivity, photosensitive surface, usually photographic film or an electronic image sensor. Th ...

and a digitally printed image, we might conclude that the digital print has photographic image quality. But subjective impressions of image quality are much more difficult to characterize and, consequently, nearly impossible to quantify. It is not difficult to demonstrate that people use multiple visual factors or

dimensions In physics and mathematics, the dimension of a mathematical space (or object) is informally defined as the minimum number of coordinates needed to specify any point within it. Thus, a line has a dimension of one (1D) because only one coordi ...

in complex

non-linear In mathematics and science, a nonlinear system (or a non-linear system) is a system in which the change of the output is not proportional to the change of the input. Nonlinear problems are of interest to engineers, biologists, physicists, mathe ...

combinations to make judgements about image quality. There are also significant individual differences in their judgements.

Image fidelity in photography

In photography, image fidelity is also referred to as micro-contrast or 3D pop. The inner tonal rendition of an image could be found as more shades and details are rendered. There are three ways to increase image fidelity. The first is to adopt a high transmission

lens A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements'') ...

on the camera. Lenses with high transmissive characteristics can direct more light into the

sensors A sensor is often defined as a device that receives and responds to a signal or stimulus. The stimulus is the quantity, property, or condition that is sensed and converted into electrical signal. In the broadest definition, a sensor is a devi ...

. The second is to increase the sensor saturation. There are two ways do this: * Reduce the thickness of the filter array on the camera sensor so that more low-gain light can be recorded * Increase the light on the subject so that the sensors are more saturated. The latter is more common.

Flash Flash, flashes, or FLASH may refer to: Arts, entertainment, and media Fictional aliases * The Flash, several DC Comics superheroes with super speed: ** Flash (Jay Garrick) ** Barry Allen ** Wally West, the first Kid Flash and third adult Flash ...

is usually the method used to achieve it. Third, reducing or removing the color filter array on a camera sensor. To remove or reduce the thickness of the filter array on the

camera sensor An image sensor or imager is a sensor that detects and conveys information used to form an image. It does so by converting the variable attenuation of light waves (as they pass through or reflect off objects) into signals, small bursts of curren ...

so that more low-gain light can be recorded. This process is also called "

Debayering Demosaicing (or de-mosaicing, demosaicking), also known as color reconstruction, is a digital image processing algorithm used to reconstruct a full color image from the incomplete color samples output from an image sensor overlaid with a color fil ...

a sensor".{{Cite web, last=Design, first=Wild Dog, date=2017-09-22, title="Monochroming" a colour sensor and colour photography with the Monochrom - Wild Dog Design, url=https://wilddogdesign.co.uk/blog/monochroming-colour-sensor-colour-photography-monochrom/, access-date=2020-12-03, language=en-GB

Image fidelity in photography

References

Further reading