Photographic Examples Research Articles

Diagnosing Early Glaucoma With Nerve Fiber Layer Examination

Those who are willing to make a modest effort... will be rewarded by acquiring an important new skill for glaucoma diagnosis, begins this well-written, superbly illustrated, stepwise course in nerve fiber examination. This short (178-page) booklet is essential reading for anyone who desires to acquire this skill. The booklet starts with an introductory chapter to bring all readers up to speed regarding the anatomy and appearance of the nerve fiber layer. Photographic examples of the changes in the nerve fiber layer caused by glaucoma are then shown. A grading system is presented and illustrated. A test set of 100 photographs is then provided along with the correct answers, so that the reader can refine the skills required in the clinical setting. This section, which allows the reader to practice and to gain confidence, provides the heart of the booklet and makes it a hands-on course in nerve fiber layer examination.

Fungal decay in oak building timbers

Discusses the forms of decay that can affect oak heartwood, sapwood and wet oak. Examines white rot fungi and brown rot fungi, in particular the way in which they attack oak, giving photographic examples of various types of attack. Considers which forms of rot have structural significance for buildings.

Maintenance of joint sealants and glazing systems

Comments on the use of mastics and sealants in building construction. Speculates that there were unrealistic claims made about the products. Discusses cause and effect of seal failures. Explains how preventive maintenance can avoid problems of water seepage. Offers and comments upon photographic examples of sealant failure. Concludes that regular inspection will warn of an impending problem and save money. Warns that remedial work should be carried out by a specialist firm.

Evaluation of Laryngeal Calcium Deposition: A New Methodology

Despite study for over 100 years, sites and patterns of laryngeal calcification and ossification are understood incompletely. Methodologies used in the past have included radiographic imaging and histologic staining with hematoxylin and eosin. Investigation of this subject offers potential application in the correlation of laryngeal disease with loss of normal calcification patterns. A technique for the detection of calcium deposition in human larynges, formerly used only in staining bony and cartilaginous tissue of small vertebrates, is described. This technique offers the advantage of whole organ staining and provides a sensitive means of determining degree and pattern of laryngeal calcification. The results of our pilot investigation with photographic examples are presented.

Managing conservation: the case of the small town

Abstract This viewpoint is based around the Council of Europe International Conference on Managing Conservation — The Case of the Small Town, held in Brittany, France in June 1986. The more important questions raised at the conference are discussed, with photographic examples of some of the outstanding restoration carried out in Brittany's historic towns.

Atlas of Skin Repair

This large-format volume presents, in an illustrated pictorial atlas, a comprehensive review of skin repair ranging from very simple techniques to complicated flap methods of reconstruction. The photographic illustrations are black and white and generally of excellent quality and clarity. The illustrations are easily understood line drawings that correlate well with the photographic examples in the accompanying text. The paper used in the atlas is of heavy weight and the nonglossy printing technique is particularly easy to read. The book seems to be well constructed and uses durable, if not top-of-the-line materials (this is not a criticism in these times of expensive printing costs and such appropriate cost-saving methods are appreciated by the reader). The volume is divided into two basic parts. The first section is devoted to general principles in techniques of skin repair. Discussion of alternatives for appropriate repair is covered both in text as well as in

Intensity Attenuation and Enhancement in 3-beam Diffraction

Abstract A simplified version of the x-ray dispersion surface is described for use in the interpretation of simultaneous 3-beam Borrmann diffraction photographs. Examples of such photographs are discussed and analyzed in terms of the simplified dispersion surfaces.

Photography of comets 1973f (Kohoutek) and 1974b (Bradfield) at Mauna Kea observatory

A catalog and examples of photographs of Comets Kohoutek (1973f) and Bradfield (1974b) made at Mauna Kea Observatory in Hawaii are given. Some photographs were obtained with an Aero Ektar ƒ/2.5 lens of 305-mm focal length, but most were made with a Celestron ƒ/1.5 Schmidt camera, also of 305-mm focal length.

A camera for photography of atomospheric particles from aircraft

A special camera has been installed on a research sailplane to take in situ photographs of atmospheric particles. Ice particle shapes, sizes, and concentrations; raindrop sizes and concentrations; and estimates of cloud droplet concentrations and maximum sizes are obtained from the photographs. The camera is capable of photographing particles as small as about 4 μ radius; the size of the largest particle completely imaged is limited by the 24×36 mm projected area photographed. Liquid particles can be distinguished from ice particles for radii greater than 50 μ. Techniques are described for calibrating the camera so that both in-focus and out-of-focus images are used for obtaining concentration and size data. Examples of photographs of ice particles, raindrops, and cloud droplets are shown. Camera improvements for getting more data for a given length of flight are suggested.

Light Fastness Evaluation of Colour Photographs

AbstractThe light fastness on the British Standard (B.S.) scale of a variety of examples of colour photographs, both transparencies and prints, has been determined and the possible lifetimes under normal conditions, before fading is noticeable, have been estimated.In transparencies from reversal films there appears to be a correlation between emulsion speed and speed of fading: the slowest film gives the best fastness, its colours are graded about 4 (on the B.S. scale of J to 8) in medium shade depths. This is probably adequate for occasional projection, though poor by textile standards, corresponding with a possible useful life of about 4 hours under continuous exposure in a modern projector. The fastest reversal films (l00 ASA and above) are very poor indeed and are graded about J on the scale, corresponding with a possible useful life of only about 0.5 hours in a projector.Colour-developed paper prints are graded between J and 2, and estimated to have a useful life of between 4 and 12 months under cont...

The Application of Spatial Filtering Techniques to Profile Inspection, and an Associated Interference Phenomenon

Profile images of cylinders and spheres produced by conventional methods of optical inspection are frequently flanked by systems of interference fringes. This phenomenon is analysed theoretically and the results are confirmed by experiment. The conclusions are relevant not only to unfiltered inspection systems but also to those employing spatial filtering techniques. In discussing the latter, a distinction is drawn between thin specimens, for which the design of spatial filter is unrestricted, and those of finite radius, for which the filter design must be carefully optimized. It is shown that the central minimum of the spatially filtered pattern delineates the true edge only if the radius of the specimen is zero. In other circumstances the positional error is a function of the cube root of the radius of the specimen and is predictable. The applicability of spatial filtering to profile microscopy and profile projection is discussed. Photographic examples of screw-threads taken with two-dimensional filters...

Holographic recording using frequency-doubled radiation at 530 nm

This paper sets out some arguments for the use of the green second harmonic (frequency doubled) radiation from a pulsed neodymium laser as the light source in recording transilluminated objects by holography, and gives in some detail a description of one experimentally realized embodiment of the idea. Examples of photographs of reconstructions of complicated three-dimensional shock waves in air are included.

Radar analysis of warm rain showers

Two X-band radar sets, an M-33 and a GPG-1, were operated routinely on the island of Hawaii during the period July 11 through August 28, 1965. The M-33 was located at the Cloud Physics Observatory on the Hilo Campus of the University of Hawaii. The data obtained from the PPI scope photography were used to determine preliminary climatological parameters associated with trade wind showers. The relationship between echo frequency and total rainfall was examined and found to be remarkably good. Such an analysis is useful in the determination of rainfall amounts over the land and over the ocean in the vicinity of Hawaii where the raingage density is sparse. The frequency of echoes of a given diameter as a function of range was tabulated according to whether the echo was observed over land or over water. It is apparent from these data that there was a greater frequency of echoes per unit area over land than over water. This is attributed to the breakup of organized lines or bands of showers as they moved inland. In addition, there is a distinct decrease of echo frequency with range. The observed decrease of echo frequency cannot be accounted for by range attenuation or atmospheric refraction. The relationship between echo movement and the trade winds was studied. The results indicate that the radar echoes tend to move to the right of the wind direction with a slightly greater speed than the environmental wind. Selected examples of radar photographs are presented which illustrate typical echo displays. In addition, the radar presentation of a mesosystem and the echoes associated with a Hawaiian thunderstorm are shown. The GPG-1 radar was located at 2100 meters on the windward slope of Mauna Kea. Very little useful data were obtained from this location due to trapping gradients associated with the trade inversion. An example is shown where the propagation path was extended and the sensitivity reduced by refractive index gradients. The site was abandoned early in the project in favor of a more concentrated effort on the M-33 operations.

A Modification of the Scanning X-Ray Topographic Camera (Lang's Method)

AbstractA modification of the scanning X-ray topographic camera, is reported. The specimen and photoplate are traversed back and forth independently in two directions rather than in the same direction as in the case of Lang’s camera. The distortions of the photographs caused by geometrical arrangement can be eliminated through this construction so as to have a one-to-one correspondence. Examples of reflection photographs as well as transmission photographs are shown. Some of them are compared with those taken using Lang’s camera. The dislocation images in the reflection photographs show a good one-to-one correspondence to those in the transmission photographs. The broadening of the dislocation images in the traversing direction is discussed. The present camera is especially useful for the studies of lattice defects in the thick specimens because the reflection photographs can be easily taken.

A high temperature single-crystal x-ray camera

A simple microfurnace is described which has been used on a standard oscillation camera for high temperature single-crystal x-ray studies. The furnace incorporates an element of fine platinum-13% rhodium wire. Examples of x-ray photographs obtained with the high temperature x-ray camera are presented.

New Emission X-Ray Microscope

A new x-ray microscope described here uses x rays emitted by substances under electron bombardment. A pinhole formed by four knife edges is used for the projection. The purpose of this microscope is similar to that of the scanning electron microscope. The resolving power of about 0.45 μ was obtained by a comparatively simple apparatus. The construction, operation, resolution, and contrast of photographs obtained with the microscope are discussed, and, for comparison, examples of photographs are shown together with conventional optical micrographs.

Polyester and Epoxy Based Non-Solvent Coatings for Corrosion Control

Abstract Discusses non-solvent coatings based on polyester and epoxy resins that give thicker film thicknesses in one application than do conventional solvent type coatings. Briefly describes special spraying equipment required for these non-solvent systems. Suggested application procedure is given. Comparison data are given on shrinkage rates of non-solvent and solvent type epoxies. Cost comparisons are made also between the two systems, showing the cost advantages derived from the thick, one-coat applications obtainable with the non-solvent coatings. Photographic examples are given of applications using the non-solvent coatings. Tabular data are included on chemical resistance of non-solvent and solvent types of epoxy coatings after a six-month continuous immersion test on sandblasted steel coupons. 5.4.5

Instrument for Thermal Photography*

The paper describes an instrument for taking thermal photographs utilizing infrared radiation passively emitted by objects at ambient temperature. The instrument consists of an 8-in. radiometer utilizing thermistor infrared detectors and an imaging attachment. A glow modulator forms a thermal photograph on Polaroid or conventional film.Quantitative analysis of thermal photographs is described, and several examples of thermal photographs are given.

The Measurement of High Speed Air Velocity and Temperature using Sound Wave Photography

SummaryA transient sound wave is generated by discharging a spark in an air stream, the velocity and temperature of which are required. After a time interval of about 25 microseconds a shadowgraph photograph of the sound wave is taken; a second photograph is obtained after a further known time interval of the same order. The two exposures, both on the same negative, show the propagation of the sound wave in the air stream and from this the Mach number, the true velocity, the local velocity of sound, and hence the temperature, can be calculated.Using this method, measurements of Mach numbers of the order of 0·5 gave values between 98 per cent, and 100 per cent, of those calculated from pressure measurements. Typical examples of the sound wave photographs are shown. With further development along the lines indicated in the paper greater accuracy should be possible. The local speed of sound was measured to an estimated accuracy of ±1·5 per cent.Since only a very short time interval is needed to obtain the photographs, the method appears promising for investigating explosions of brief duration, or dealing with flows of pulsating character.

The Typical Perseid Meteor Spectrum

THE first Perseid meteor spectrum was photographed by S. Blajko at Moscow on a blue-sensitive plate on August 12, 19041,2; but up to 1934 only two additional examples of such photographs had been secured. The emission lines of Fe I, Ca I, Ca II, Mg I, Mn I and Al I were identified in the early photographic spectra, the H and K lines of Ca II generally being the strongest feature.