[en] Analogous and digital techniques for evaluation of autoradiograms are compared and measured for critical evaluation of autoradiograms. Additional instruments to a Zeiss-Photometer for digital and analogous evaluation of autoradiograms are described. (author)

[en] Results of the U, B and V photometry of galaxies in the cluster Zw 1305.4 + 2941 are presented. The cluster has a redshift of 0.24 and the photometry is referred to the galaxies inside the region of radius 1.2 Mpc from the cluster center. To produce these results, an automated reduction procedure was applied to the microdensitometer data obtained scanning a region of Palomar 48 in. plates. These procedures include a segmentation process, smoothing, calibration of the plates using standard stars profiles and magnitudes and a star-galaxy classification

No abstract available

[en] Multi-beam gamma densitometers are commonly used to determine the average void fraction and phase distribution in two-phase flow experiments. A simple, reliable and efficient algorithm is developed to determine the void fraction and flow regime from the experimental data. The algorithm was first tested on idealized and realistic flow situations, where the chordal and average void fractions, and phase distributions were known exactly. Results were found to be in excellent agreement with the exact flow cases. Then, a comparison with a previous technique was made using experimentally obtained input. The present scheme required considerably less computational time and yielded comparable results. (author). 4 refs., 6 figs

[en] A method of reading exposed radiochromic film is described which has significant advantages over conventional densitometry. The method employs a document scanner and associated software for imaging the film. The resulting images are easily analysed using standard software to yield high-resolution dose maps. A calibration was performed which relates scanner signal to dose, allowing for the determination of dose at any point on an exposed film. Results obtained using a broad-band densitometer are compared to those where the scanner has been used. The technique was used to measure the dose distribution around a COMS-type ophthalmic applicator. (author)

[en] A rather simple autoradiographic method for evaluation and documentation is described. (author)

No abstract available

[en] An x-ray photodensitometer provided accurate and precise measurements of linear dimensions on radiograph images. These measurements helped to infer the hidden dimensions of objects radiographed. A goal was to achieve an accuracy of +-25 μm. The recorded accuracy did not measure up to the precision, which, under favorable conditions, was +-25 μm. Systematic errors caused the errors in absolute value to be considerably higher in some cases. To satisfy this, auxiliary calibrations were made. Many deterrents to successful measurement arose. These included film grain noise, excessive density range and edge penetration, blurring, interfering structures, and scattered radiation. Film grain noise, in particular, limited the resolution of small details (fine structure) in a radiograph. Because of so many deterrents, the applicability of the measurement method used appears quite limited

No abstract available

[en] This report describes the principle of a method for quantifying defects on metal parts obtained by casting. It is based on the relation expressing the optical density of the image according to the thickness of the material. The three techniques used, to wit: gammagraphy, microdensitometry and data processing, are presented, as is the equipment used and the methodology adopted