scholarly journals On the Problem of Standard Fields for CCD Astrometry

1995 ◽  
Vol 167 ◽  
pp. 353-354
Author(s):  
I. S. Guseva
Keyword(s):  
Focal Length ◽  
Field Of View ◽  
Proper Motions ◽  
Angular Scale ◽  
Ccd Observations ◽  
Photometric Measurements ◽  
Angular Field Of View

At the start of CCD observations one must investigate the metrological properties of the complex instrument: optics + CCD. One needs a densely spaced set of stars with precise coordinates and magnitudes. We first used the Pleiades catalogue by Eichhorn et al. (1970). Experimental observations were started at Pulkovo in 1993 using a very small refractor (D = 100 mm, F = 712 mm) equipped with a CCD ISD015A (520 × 580 pixels, 18 × 24 microns). The focal length of our astrograph provides an angular field of view of 45 × 67 arcmin (angular scale is 5.2 × 7 arcsec/pixel). With different exposures we can observe all stars with magnitudes from 2 to 16. The first observations were made to evaluate the accuracy of our positional and photometric measurements. Unfortunately, it appears that the catalogue of the Pleiades by Eichhorn is not good enough for this purpose because its epoch is very far from that of our observations and proper motions were not provided for the majority of the stars. The internal precision of our measurements (0.1–0.3 arcsec) allows us to determine the corrections to the stellar positions by Eichhorn et al. (1970)

scholarly journals IMPROVEMENT OF THE METHOD OF MEASURING ANGULAR FIELD OF VISION OF AN OPTICAL SIGHT

2020 ◽  
Vol 6 (1) ◽  
pp. 181-188
Author(s):  
Maxim E. Kobzar ◽  
Aelita V. Shaburova
Keyword(s):  
Field Of View ◽  
Measuring Instrument ◽  
Practical Application ◽  
Instrument Making ◽  
Field Of Vision ◽  
Quality Of Products ◽  
The Moment ◽  
Site Training ◽  
Angular Field Of View

The article discusses the practical application of the method of measuring the angular field of view of an optical sight using theodolite. «Novosibirsk Instrument-Making Plant» is one of the largest manufacturers of shooting and observation optics throughout Russia. To improve the quality of products manufactured at the plant (optical and hunting sights, binoculars, telescopes, monoculars, etc.), it is necessary to verify the main technical characteristics during their production using an approved type measuring instrument. At the moment, the measurement of the angular field of view at the enterprise of JSC "NPZ" is carried out at a specialized site (training ground). This technique will allow testing on-site. The article describes an experiment in the course of which the results were obtained, according to which it can be concluded that this technique is suitable for measuring the angular field of view.

scholarly journals DEVELOPMENT OF THE METHOD OF PERFORMANCE OF MEASUREMENTS OF ANGULAR FIELD OF VIEW OF OPTICAL PRODUCTS

2019 ◽  
Vol 6 (1) ◽  
pp. 227-230
Author(s):  
Maxim Kobzar ◽  
Valery Pavlenko
Keyword(s):  
Field Of View ◽  
Measuring Instruments ◽  
Angular Field Of View

The article deals with the problem of the lack of a technique for measuring the angular field of view of optical products, using approved-type measuring instruments.

Visibility of the phantom array effect according to luminance, chromaticity and geometry

2019 ◽  
Vol 52 (3) ◽  
pp. 377-388
Author(s):  
SW Park ◽  
C-S Lee ◽  
HR Kang ◽  
HS Pak ◽  
A Wilkins
Keyword(s):  
Light Source ◽  
Pulse Width Modulation ◽  
Light Emitting Diode ◽  
Field Of View ◽  
Light Sources ◽  
Experimental Conditions ◽  
Threshold Frequency ◽  
Automotive Lighting ◽  
Lighting Systems ◽  
Angular Field Of View

Light-emitting diode-based lighting systems are now applied in both general lighting and automotive lighting. Time-modulated control methods such as pulse width modulation are frequently applied as a dimming method. This paper presents the characteristics of the visibility of the phantom array effect according to luminance, chromaticity and angular field of view. The threshold frequency of the visibility of the phantom array increases in proportion to the logarithm of the luminance of the light source. As the angular field of view of the light source increases, the threshold frequency of the visibility of the array decreases exponentially over a range from 0.125° to 4° in our experimental conditions. The threshold frequency at which the array is visible depends on chromaticity at high light source modulation frequencies. When designing time-modulated light sources, our findings can be applied so as to minimize the phantom array effect.

A Variable Angular Field-of-view Transmissometer and Its Use to Monitor Fog Conditions

1984 ◽  
Vol 31 (5) ◽  
pp. 589-601 ◽  
Author(s):  
P. Bruscaglioni ◽  
G. Del Fante ◽  
A. Ismaelli ◽  
L. Lo Porto ◽  
G. Zaccanti
Keyword(s):  
Field Of View ◽  
Angular Field Of View

scholarly journals Technical note: Scintillations of the double star α Cru observed by GOMOS/Envisat

2009 ◽  
Vol 9 (22) ◽  
pp. 8967-8973 ◽  
Author(s):  
V. F. Sofieva ◽  
F. Dalaudier ◽  
V. Kan ◽  
A. S. Gurvich
Keyword(s):  
Light Source ◽  
Technical Note ◽  
Double Star ◽  
Field Of View ◽  
Atmospheric Air ◽  
Qualitative And Quantitative ◽  
Double Structure ◽  
Air Density ◽  
Quantitative Explanation ◽  
Angular Field Of View

Abstract. In this paper, we discuss scintillation time-spectra of the double star α Cru, which were measured by the GOMOS/Envisat photometer. The components of α Cru are not resolved by the angular field of view of the detector. The double structure of the light source reveals itself in the modulation of the observed scintillation spectra; this modulation is caused by anisotropic irregularities of the stratospheric air density. We present a qualitative and quantitative explanation of the properties of the double-star scintillation spectra. Possibilities of using double star scintillations for studying atmospheric air density irregularities are also discussed in the paper.

Angular field of view for Brillouin amplification

1993 ◽  
Author(s):  
Yaakov Glick ◽  
Shmuel Sternklar
Keyword(s):  
Field Of View ◽  
Angular Field Of View
Sign in / Sign up

Export Citation Format

Share Document