Tone Reproduction

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Tone Reproduction


in photography, the transmission to a photographic image of the differences in brightness (B) of details in the subject photographed. The differences are rendered as differences in optical density (D) in the image.

With ideal photographic tone reproduction in the final positive image, whether a print or diapositive, the differences in D for any two details should be such that the ratio of brightnesses in the subject and the image are identical under identical conditions of examination. Such tone reproduction is effected only if the entire sequence of conversions is linear and if the range in which the conversions take place is unlimited. The entire sequence includes the conversions of the set of brightnesses to the set of illuminations on the negative emulsion and, subsequently, to negative blackening, illumination on the positive emulsion, positive blackening, and so on, to the set of blackenings on duplicates or the set of illuminations on a viewing screen. In practice, however, all the stages of the photographic process are more or less nonlinear and are limited in range. For example, the characteristic curve of the photosensitive emulsion is always nonlinear, and its exposure latitude is limited and insignificant, even compared to the complete range of transmitted exposures.

Tone reproduction is complicated even more if the image is evaluated visually, rather than by means of objectively measured characteristics. In this case, the number of distorting factors is increased to include the characteristics of the eye as a receiver, which may evaluate the same set of values of B differently, depending on the size of the details, the various illumination levels of the image and the subject, and uneven darkening in the room used for examination. As a result, the basic problems in the theory of tone reproduction are no longer seen as the determination of conditions for ideal tone reproduction. Rather, by necessity, they have gradually been reformulated as the determination of conditions under which tone reproduction is still satisfactory for the possible wider range of values B as the analysis of how to reproduce a given subject photographically with the smallest degree of distortion of the differences in B, and as the determination of quantitative estimates of such distortion.


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Proper photographic tone reproduction and maximum fine line detail retention are required to ensure that the historical information captured so carefully in the past will still be available for future generations.
The mapping techniques from the HDR images to the LDR display devices are called tone mapping or tone reproduction [5].
Equipped with the 12 LUCIA pigment ink system, the PIXMA Pro-1 boasts of a color range that has improved saturation of colors and darker, deeper blacks, allowing him to achieve new levels of skin tone reproduction, accuracy and quality.
It also delivers incrediA[degrees]ble resolving power for high quality results that are enhanced by the unique skin tone reproduction technology found in Fujifilm's XA[degrees]mount cameras.
It also delivers incredible resolving power for high quality results that are enhanced by the unique skin tone reproduction technology found in Fujifilm's X-mount cameras.
Modulation of lightness in neutrals as well as saturated colors, combining primaries and black lead to various facilities of possible tone reproduction curves, in addition to printing reproduction features.
The basic colorimetric characterization of the CRT monitor can be represented as a combination of two parts: the tone reproduction curves (TRCs) for each channel, and the transformation matrix from linearized RGB to tristimulus values (XYZ).
94-micron pixel size and high signal to noise ratio produces vibrant images with breathtaking image fidelity while reducing lost highlights and shadows, and ensuring smoother tone reproduction with minimized noise.
However, the inkjet ink printed cotton fabric needed to be printed three times to produce the same colour and tone reproduction as that produced by screen printing.
Because the dots used in FM screening are so tiny, he said, even the slightest growth in size can throw off tone reproduction curves, reducing print contrast and hurting detail in both the highlight and three-quarter tones of an image.
With mechanical dot gain arising from ink spreading at dot edges, stochastic screening uses the tone reproduction curve to remove some dots to achieve the desired optical density, leading to "the potential to save up to 20% of ink" for a given product, said Willis.
Frey (1997) suggests that four targets be used for objectively evaluating the results of digitization: tone reproduction, color reproduction, detail and edge reproduction, and noise.