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To subclassify pseudodrusen based on their appearance in multimodal imaging.Retrospective, observational series.The color fundus photographs and infrared scanning laser ophthalmoscope (IR-SLO) images of patients with pseudodrusen were evaluated along with spectral-domain optical coherence tomography (SD OCT) by masked readers. Distinct types of pseudodrusen could be differentiated.There were 140 eyes of 93 patients with a mean age of 82.4 years. Multimodal imaging analysis showed 3 subtypes of pseudodrusen. One principal type was an orderly array of whitish discrete accumulations principally located in the perifovea, termed dot pseudodrusen. They appeared as hyporeflective spots, often with a target configuration, in IR-SLO images. The second type was interconnected bands of yellowish-white material forming a reticular pattern, called ribbon pseudodrusen, which were located in the perifovea. This subtype was faintly hyporeflective in IR-SLO imaging. Dot pseudodrusen were detected more commonly with IR-SLO imaging than in color photography (P = .014) and ribbon pseudodrusen were seen more frequently in color than in IR-SLO images (P.001). An uncommon third type of pseudodrusen, yellow-white globules primarily located peripheral to the perifoveal region, appeared hyper-reflective in IR-SLO and were called peripheral pseudodrusen. All 3 types were seen as subretinal drusenoid deposits by SD OCT.Pseudodrusen may be classified into at least 3 categories, each with optimal methods of detection and only 1 that formed a reticular pattern. These findings suggest pseudodrusen could contain differing constituents and therefore may vary in conferred risk for progression to advanced age-related macular disease.

In this paper we present a comparative analysis of three vision systems to nondestructively predict defects on the surfaces of aluminum castings. A hyperspectral imaging system, a thermal imager, and a digital color camera have been used to inspect aluminum metal cast surfaces. Hyperspectral imaging provides both spectral and spatial information, as each material produces specific spectral signatures which are also affected by surface texture. Thermal imager detects infrared radiation whereby hotspots can be investigated to identify possible trapped inclusions close to the surface, or other superficial defects. Finally, digital color images show apparent surface defects that can also be viewed with the naked eye but can be automated for fast and efficient data analysis. The surface defect locations predicted using the three systems are then verified by breaking the casings using a tensile tester. Of the three nondestructive methods, the thermal imaging camera was found to produce the most accurate predictions for defect location that caused breakage.

A survey of the researches of James Clerk Maxwell into the production and perception of colour is presented, and links to a selection of present day applications of colour science are indicated. Although false colour photography was not known in Maxwell's time, aspects of his work, suitably interpreted, have a bearing on the wide applicability of the technique. An outline is given of one application of false colour to visualising and analysing data on fluid motion.

Summary The present article includes the theoretical interpretation, description and verification of the suggested method for measurement of granularity of colour photographic films. The corresponding designed and realized device is based on the uniform low-speed rotation of the suitable enlarged light-permeable photographic copy of measured structural granularity and on the microphotometric scanning of its optical image. The obtained electrical analog signal is amplified and converted to the digital form and then electrically processed by a special electronical system. It is a modern digital rotational microphotometrical granulometer of the module conception with optical separation of control signals and with originally designed rotating mechanical sample stage and electronical processing system which is useful for the laboratory practice. Its resulting outputs consist of random optical transmittance or optical density data of a sample under measurement, their mean value and dispersion.

A new method to obtain the three-dimensional information on nuclear tracks was developed using color photography. Commercial color films were irradiated with ion beam and color-developed. The ion tracks were represented with color images in which different depths were indicated by different colors, and the three-dimensional information was obtained from color changes. Details of this method are reported, and advantages and limitations are discussed in comparison with a conventional method using a nuclear emulsion.

Part 2 deals with magenta and cyan couplers and—in addition—white couplers and scavengers, centred about the years between 1960 and 2000 as in Part 1.Magenta couplers have been a domain of heteroar...

Rudolf Fischer's concept of ‘chromogenic development’ of sensitized silver halide, which used only one colour developer for producing the triad of subtractive primaries yellow—magenta—cyan in the p...

The early experiments of Hiedemann on light diffraction led to an understanding of many experimental aspects of the subject, and defined many topics for further investigation. The theory of Raman and Nath broadened the understanding and defined many concepts that were not apparent to the experimenter. Although this theory is basically correct, it has been revised and improved over the years. The transition between Raman-Nath and Bragg diffraction was illuminated by the definitions of Klein, Cook and Mayer. Initially, the main focus of many investigations was on light diffraction by ultrasonic waves because there are many aspects of the subject. Later, it was realized that this interaction is an ideal way to study wave phenomena generally since optical diffraction does not disturb the ultrasonic wave. The unique perspective provided by acousto-optic interactions has made this a useful tool. By imaging ultrasonic waves one can make detailed studies of ultrasonic wave interactions and apply the results to many other types of waves. With acousto-optics one can study evanescent waves, ultrasonic finite amplitude effects, Bragg diffraction, Bragg imaging, etc. The application to other systems makes this a truly formidable study. The development of modern optics has made possible the description and understanding of wave interactions that heretofore had been mysterious. This paper begins with a description of early experiments. Later, it deals with finite-amplitude effects, parametric oscillations, Bragg diffraction and Bragg imaging. The study of evanescent waves by schlieren photography is a special case. Some topics have been studied by theory and experiment; some still await an acoustical theory although an optical theory exists, along with acoustical verification. Contributions of many citizens of the USA are considered. The paper ends with the application of the modern concepts of spatial filtering and information content to the analysis of colour schlieren photography.

Lippmann colour photography has many similarities to holography. We present an analysis exploiting this similarity which shows how to optimize the recording and viewing conditions for Lippmann colour photographs.

The effect of five development-accelerator-releasing (DAR) couplers derived from different hydrazines on the photographic characteristics of color negative material has been studied It was found that the development-accelerator-releasing couplers examined may be used together with cyan couplers in a color negative material to increase the photographic speed; no apparent difference was observed with the different hydrazines.

Two development-accelerator-releasing couplers were synthesized with different conventional couplers and the effect of the two compounds on the photographic characteristics of color negative material were examined.

Red-free light allows better detection of vascular lesions as this wavelength is absorbed by hemoglobin; however, the current gold standard for the detection and grading of diabetic retinopathy remains 7-field color fundus photography. The goal of this study was to compare the ability of 7-field fundus photography using red-free light to detect retinopathy lesions with corresponding images captured using standard 7-field color photography. Non-stereoscopic standard 7-field 30° digital color fundus photography and 7-field 30° digital red-free fundus photography were performed in 200 eyes of 103 patients with various grades of diabetic retinopathy ranging from mild to moderate non-proliferative diabetic retinopathy to proliferative diabetic retinopathy. The color images (n = 1,400) were studied with corresponding red-free images (n = 1,400) by one retina consultant (PV) and two senior residents training in retina. The various retinal lesions [microaneurysms, hemorrhages, hard exudates, soft exudates, intra-retinal microvascular anomalies (IRMA), neovascularization of the retina elsewhere (NVE), and neovascularization of the disc (NVD)] detected by all three observers in each of the photographs were noted followed by determination of agreement scores using κ values (range 0-1). Kappa coefficient was categorized as poor (≤0), slight (0.01-0.20), fair (0.2 -0.40), moderate (0.41-0.60), substantial (0.61-0.80), and almost perfect (0.81-1). The number of lesions detected by red-free images alone was higher for all observers and all abnormalities except hard exudates. Detection of IRMA was especially higher for all observers with red-free images. Between image pairs, there was substantial agreement for detection of hard exudates (average κ = 0.62, range 0.60-0.65) and moderate agreement for detection of hemorrhages (average κ = 0.52, range 0.45-0.58), soft exudates (average κ = 0.51, range 0.42-0.61), NVE (average κ = 0.47, range 0.39-0.53), and NVD (average κ = 0.51, range 0.45-0.54). Fair agreement was noted for detection of microaneurysms (average κ = 0.29, range 0.20-0.39) and IRMA (average κ = 0.23, range 0.23-0.24). Inter-observer agreement with color images was substantial for hemorrhages (average κ = 0.72), soft exudates (average κ = 0.65), and NVD (average κ = 0.65); moderate for microaneurysms (average κ = 0.42), NVE (average κ = 0.44), and hard exudates (average κ = 0.59) and fair for IRMA (average κ = 0.21). Inter-observer agreement with red-free images was substantial for hard exudates (average κ = 0.63) and moderate for detection of hemorrhages (average κ = 0.56), SE (average κ = 0.60), IRMA (average κ = 0.50), NVE (average κ = 0.44), and NVD (average κ = 0.45). Digital red-free photography has a higher level of detection ability for all retinal lesions of diabetic retinopathy. More advanced grades of retinopathy are likely to be detected earlier with red-free imaging because of its better ability to detect IRMA, NVE, and NVD. Red-free monochromatic imaging of the retina is a more effective and less costly alternative for detection of vision-threatening diabetic retinopathy.

We present digitized photographs of the white-light solar corona taken during the total solar eclipse of 22–23 November, 1984, on both calibrated black-and-white film and on color film. Conditions on site in Hula, Papua New Guinea, were exceptionally clear. The color image was used to produce an isophotal map of the inner corona, from which a flattening coefficient of 0.23 was measured. The black-and-white image was enhanced through a digital radial filter. Our images are the best processed images available from the 1984 eclipse and so provide important data for synoptic observations.

For use in reflected‐light color photography a diffuse light source has been developed which has an annular geometry (347×140 mm in diameter) and coaxially surrounds the optical beam of recording. The light source has a luminous peak intensity of 200 Mcd and emits a flash with a duration of 180 ns FWHM. The principle of operation is based on a chain of nine V‐shaped light‐emitting gliding sparks, each consisting of at least 50 interstitial copper electrodes for the generation of micro gliding discharges. They are all connected in series and driven by a modified nine‐stage Marx‐surge generator. Substituting each V‐shaped gliding spark by two U‐shaped Xe‐filled flash lamps doubles the light output as well as the flash duration.

A compact optical system for use with rainbow schlieren deflectometry is described. Both halves of the optical system consist of well-corrected telescopes whose refractive elements are all from manufacturer's stock catalogs, with the reflective primary being a spherical surface. As a result, the system is relatively easy to construct and meets the requirement of long focal length for quantitative rainbow schlieren measurements.

Multispectral middle IR (8-13 microns) data were acquired with an aircraft scanner over Utah. Because these digital image data were dominated by temperature, all six channels were highly correlated. Extensive processing was required to allow geologic photointerpretation based on subtle variations in spectral emittance between rock types. After preliminary processing, ratio images were produced and color ratio composites created from these. Sensor calibration and an atmospheric model allowed determination of surface brightness, temperature, emittance, and color composite emittance images. The best separation of major rock types was achieved with a principal component transformation, followed by a Gaussian stretch, followed by an inverse transformation to the original axes.

The information content of a contour map is calculated and compared with the information required for determining the relative position of the contours. We have found that usually the information required for arranging the contours in the right order is small as compared with that of producing the map. To demonstrate this finding we introduce two novel methods for ordering the contours. The first makes use of two colors, double exposure, moire mapping. The second analyzes the relative motion of hills and valleys, while the relative angle of two transparencies photographed in the grid projection technique is changed.

Theoretical and experimental investigations on the real-time transmission of 3-D images formed by parallax panoramagrams are described. At the image-taking station, a 3-D image is optically decomposed into line images, which can be directly handled by a high resolution TV set. By registering a lenticular sheet to the reproduced line images on a monitor screen, the reconstructed 3-D image is seen by the naked eye. By using an ordinary color TV set with a 350-line resolution and a cylindrical lens array with a 3-mm pitch, 3-D color images composed of thirty-five elements in the horizontal direction and seen from four directions are successfully transmitted and reconstructed with clear parallax.

Several methods of spectral sensitivity estimation for color image scanners are developed and evaluated. The estimation procedure involves response measurements of the scanner through a set of spectrally selective filters. These measurements form the observations for generalized inverse, smoothing, and Wiener estimation processes. Wiener estimation is found to provide the best results.

The recording and reconstruction of a multicolor image from a plane hologram by spatial filtering in the Fourier plane are discussed. Conditions under which the reconstructed images are free from color crosstalk are described and analyzed. Experimental results for confirming the analysis by a two-color reconstruction is presented. The spatial filter size and the information recording capability are determined from hologram recording parameters. It is found that the resolution capability of this method is adequate for many practical applications. Methods for recording and reconstruction of multicolor images without an imaging lens are also discussed. Many possible applications are suggested.

This paper is concerned with flare measurement in photographic lenses by three colors instead of white light. The results have interesting relations to the antireflection coating, the barrel interior finishing, area and condition of the iris diaphragm of the lens, and the lens edge painting. For color photography, it is more realistic to evaluate flare by means of the relative amount present in each of the blue, green, and red color components. In accordance with the data thus measured, various countermeasures can be considered.

Multistage color photography without the usual attendant loss of color integrity is described. The technique was evolved for fabricating a four-color, patterned transparency requiring a high degree of pattern precision and close control of color characteristics. The necessary accuracy is achieved through an enlargement–reduction multistage photographic process. Color integrity is maintained through the several processing stages by means of multiple exposure through filters spectrally compatible with the film and the painted pattern.

Two daylight-balanced colour negative films, one professional and one amateur product, have been exposed to a standard subject using approximately Planckian light sources with a wide range of colour temperatures. Prints have been made to achieve a standard grey reproduction from each negative and have also been prepared using a commercial automatic printer calibrated with the negative, in each set, exposed using professional electronic flash. Subjective investigations of print acceptability are used to investigate the influence of the different spectral sensitivity distributions of the two negative films. Print acceptability is also related to a Colour Reproduction Index calculated from the standard subject, using the Hunt colour appearance model. Conclusions are drawn concerning the applicability of different subjective techniques in determining print acceptability, the effect of negative sensitivities and the applicability of the Hunt colour appearance model to problems of print acceptability.

A new technique of pseudocolor encoding of spatial filtered holographic imaging is introduced. The encoding takes place at the spatial frequency plane, and a multiwavelength rainbow holographic process is used. This technique provides a simple encoding procedure and offers a wide range of pseudocolor holographic images. The possible applications of this technique range from pseudocolor coding of aerial photography to x-ray transparencies. Because of the white-light-readout rainbow process, this technique provides a better and more natural pseudocolor image.

Two-dimensional fluorescence and lasing images of a Rhodamine-6G doped water spray are observed with color photography. The lasing microdroplets are identified by their two reciprocal lasing spots. The microdroplet sizes are measured using the digitized images. The measured mean microdroplet diameter is 69.7 μm with a standard deviation of 23.1 μm. The measured microdroplet size distribution compares favorably with the normal Gaussian size distribution.

Schlieren methods are widely known and well established to visualize refractive index variations in transparent media. The use of color allows one to obtain more data and previously inaccessible information from a picture taken with this technique. In general, a hue can be related to a certain strength or a certain direction of a refractive index gradient. While the first case essentially corresponds to the usual black- and-white system the latter correlation cannot be made adequately evident without the use of color. Two color schlieren techniques are presented here, which reach or even exceed the quality and sensitivity range of conventional black- and-white methods. Using a powerful short duration light source these methods are applied to visualize transient flow phenomena in a shock tube.

インスタントカラー写真に用いるo-スルホンアミドフェノール色素放出剤の分子設計における知見を述べる。この化合物の色素放出能力は,酸化と加水分解による。これらの効率が,ベンゼン環の置換基によって,大きく変化することを見いだした。とくに,相当する酸化体(o-キノン・モノスルホンイミド)の加水分解の副反応を調べ,それがt-ブチル基の立体障害により抑止できることを見つけた。一方,放出されるアゾ色素の堅ろう性は,アゾ成分中の電子供与基の存在で向上することを示した。色素放出剤の合成設計においては,o-アミノフェノール中間体の合成経路を種々検討した。その中から,ベンゾオキサゾールを経由する経路を開発した。Beckmann転位によるベンゾオキサゾールの合成法,スルホニルクロリドの合成条件,2-メトキシエトキシ基の導入方法,キノンの新規還元法を述べる。この研究によって,この色素放出剤を用いるインスタントカラーフィルムが,実用化された。

Electronic flash, produced by large studio lights or compact units attached to the camera or as part of the camera itself (on the Hasselblad H camera models) is the most common light source for digital or film photography. Electronic flash produces no heat; the duration of the flash is short, which reduces the danger of blurred images; and the color temperature matches that of normal daylight so the two can be combined in color photography.

Instant color photography is called diffusion transfer reversal color photography (DTR color photography) or simply diffusion transfer photography,since it is based on imagewise dye diffusion (nondiffusion) as a function of exposed silver halide. The beginning of instant color photography was the peel-apart system (Polaroid 108) placed on the market by Polaroid (1963). Afterwards, integrated (mono-sheet) systems called SX-70 (1972, Polaroid), PR-10 (1976, Kodak), and FI-10 (1981, Fuji Photo Film) appeared as more elaborate systems.1

For easy color photography, we have proposed a method of irradiating a silicon photosensor from the side. This color imaging method applies a simple pixel structure without color filters, and prevents the generation of false colors and moiré patterns. A test chip was fabricated using a 0.35 µm complementary metal–oxide–semiconductor 1-poly 4-metal process. The chip dimensions are 5000 × 5000 µm2. The pixel layout structure that we proposed previously was remodeled. We confirmed that the four colors blue, green, red, and near-infrared are isolated in the normal color wavelength range in a light irradiation experiment.

Instant color photography began in 1963 with a one-step print process providing a finished photograph within a minute after exposure. Outwardly dry processing under ambient conditions is initiated within the camera upon release of reagent from a sealed pod that is provided as part of the film unit. Integral print films, introduced in 1972, retain the developed photosensitive layers concealed within the print. Instant film configurations also include print and transparency processing independent of the camera. Subtractive instant color processes use dye-developers and dye-release compounds to generate images comprising preformed dyes. Dye-release compounds are also utilized in wet-processed reprographic films and in photothermographic films for hard copy from images generated by instruments or computers. Additive instant color transparencies comprise microscopic black-and-white silver images formed by exposure of a panchromatic emulsion layer through an integral color screen. The chemistry of the various systems is discussed. Instant color films are utilized in many professional fields, especially those involved in documentation or imaging.

This unit provides an overview of light microscopy, including objectives, light sources, filters, film, and color photography for fluorescence microscopy and fluorescence in situ hybridization (FISH). We believe there are excellent opportunities for cytogeneticists, pathologists, and other biomedical readers, to take advantage of specimen optical clearing techniques and expansion microscopy-we briefly point to these new opportunities. © 2017 by John Wiley & Sons, Inc.

High speed photography for range testing often requires intense disposable illumination sources. A low cost surface discharge source is being developed to replace argon candles for many range tests. Since the test environment will likely destroy the lamp, it is fabricated from inexpensive materials and does not require machining of any components. A series of tests were performed to determine the radiative output in the visible of candidate surface discharge lamps, and to clarify the illumination requirements. Tests using a range camera and a short pulse 100 cm2 planar surface discharge determined that an irradiance of 600 W/cm2 on target is sufficient for black and white photography at 2 million fps whereas color photography requires approximately 3 kW/cm2. The results of the subscale tests have been used to guide development of a full scale pulse forming network (PFN) matched to a set of surface discharge lamps. The PFN delivers 12 kJ to the lamps in pulses that can range from 40 microseconds to 1 ms. The matching lamps have been developed and tested for pulse lengths as long as 200 microseconds.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A high-speed digital streak camera designed for simultaneous high-resolution color photography and focusing schlieren imaging is described. The camera uses a computer-controlled galvanometer scanner to achieve synchroballistic imaging through a narrow slit. Full color 20 megapixel images of a rocket sled moving at 480 m/s and of projectiles fired at around 400 m/s were captured, with high-resolution schlieren imaging in the latter cases, using conventional photographic flash illumination. The streak camera can achieve a line rate for streak imaging of up to 2.4 million lines/s .

We investigate the possibilities of light detection and ranging (lidar) techniques to study migration of the damselfly species Calopteryx splendens and C. virgo. Laboratory and testing-range measurements at a distance of 60 m were performed using dried, mounted damselfly specimens. Laboratory measurements, including color photography in polarized light and spectroscopy of reflectance and induced fluorescence, reveal that damselflies exhibit reflectance and fluorescence properties that are closely tied to the generation of structural color. Lidar studies on C. splendens of both genders show that gender can be remotely determined, especially for specimens that were marked with Coumarin 102 and Rhodamine 6G dyes. The results obtained in this study will be useful for future field experiments, and provide guidelines for studying damselflies in their natural habitat using lidar to survey the air above the river surface. The findings will be applicable for many other insect species and should, therefore, bring new insights into migration and movement patterns of insects in general.

The analysis and performance of a high-brightness large-field focusing schlieren system is described. The system can be used to examine complex two- and three-dimensional flows. Techniques are described to obtain focusing schlieren through distorting optical elements, to use multiple colors in a time multiplexing technique, and to use diffuse screen holography for three-dimensional photographs.

A corona discharge photography system using a transparent electrode, which allowed removing the film from the discharge, was constructed. Color photographs were produced from the discharge on various object electrodes. It is shown that the color is dependent on the material within the discharge, and that the "engineering" of the color pattern is feasible.

— Images have been produced by modulating light by diffraction for over 100 years. Two Nobel prizes have been awarded for imaging techniques using diffraction. The modulation efficiency is quite high, and diffraction can be used to select the color as well as the intensity of an image. The process does not require polarized light. A wide variety of light modulators can be used to produce efficient diffractive images. This paper intends to follow the history of the use of diffraction to produce images and describe some of the newer techniques that have the potential of extending the use of diffractive imaging far into the future.

The Foundations of Holography The roots of holography stem back to the work of Lippmann, who, in 1891, published a method of storing permanent color photographs as refractive index modulation in a thick layer of emulsion [1]. In his technique, a layer of mercury is placed on the back of the emulsion so as to reflect the incident light that forms a standing-wave interference pattern that is then recorded in the layer. This method produces the same distribution of wavelength components as the original light from one angle of view. The available literature on the development of Lippmann color photography [2] includes a publication by Cotton, who wrote

An experiment to measure the polarization of land, sea, haze, and cloud areas from space was carried aboard the Space Shuttle in Sept. 1985. Digitized polarimetric and photometric imagery in mutually perpendicular planes was derived in the red, green, and blue spectral regions from photographs taken with two synchronized Hasselblad cameras using type 5036 Ektachrome film. Digitization at the NASA Houston Video Digital Analysis Systems Laboratory permitted reduction of the imagery into equipolarimetric contours with a relative accuracy of +/-20% for comparison to ground truth. The Island of Hawaii and adjacent sea and cloud areas were the objects of the specific imagery analyzed. Results show that cloud development is uniquely characterized using percent polarization without requiring precision photometric calibration. Furthermore, sea state and wind direction over the sea could be inferred as well as terrestrial soil texture.