Related papers: CCD photometry of bright stars using objective wir…
We present a new method to measure the vertical aerosol optical depth (VAOD) during clear nights using a wide-field imager - a CCD camera with a photographic lens on an equatorial mount. A series of 30-second exposures taken at different…
We have constructed a large format mosaic CCD camera for the Sloan Digital Sky Survey. The camera consists of two arrays, a photometric array which uses 30 2048 x 2048 SITe/Tektronix CCDs (24 micron pixels) with an effective imaging area of…
We show the astrometric potential of the Wide Field Imager at the focus of the MPI-ESO 2.2m Telescope. Currently, we are able to measure the position of a well-exposed star with a precision of $\sim$4 mas/frame in each coordinate (under 0.8…
Photographic plate archives contain a wealth of information about positions and brightness celestial objects had decades ago. Plate digitization is necessary to make this information accessible, but extracting it is a technical challenge.…
The idea of using stellar photometry for atmospheric monitoring for optical experiments in high-energy astrophysics is seemingly straightforward, but reaching high precision of the order of 0.01 in the determination of the vertical aerosol…
Visual photometry, the estimation of stellar brightness by eye, continues to provide valuable data even in this highly-instrumented era. However, the eye-brain system functions differently from electronic sensors and its products can be…
We use differential CCD photometry to search for variability in BVI among 990 stars projected in and around the old open cluster M 67. In a previous paper we reported results for 22 cluster members that are optical counterparts to X-ray…
We have developed a method to measure the mirror reflectivity of telescopes. While it is relatively easy to measure the local reflectivity of the mirror material, it is not so straightforward to measure the amount of light that it focuses…
The description is given for the speckle interferometer of the BTA 6-m telescope of the SAO RAS based on a new detector with an electron multiplication CCD. The main components of the instrument are microscope objectives, interference…
We present some results of testing of commercial color CMOS cameras for astronomical applications. CMOS sensors allow to perform photometry in three filters simultaneously that gives a great advantage compared with monochrome CCD detectors.…
We have conducted a 1.5 year-long variability study of the stars in the Cygnus OB2 association, the region in the northern hemisphere with the highest density of optically visible massive stars. The survey was conducted using four pointings…
Herein, we describe the design, implementation and operation principles of an astronomical camera system, based on a large-format CCD261-84 detector with an extremely thick 200 mkm substrate. The DINACON-V controller was used with the CCD…
High precision astrometry requires an accurate geometric distortion solution. In this work, we present an average correction for the Blue Camera of the Large Binocular Telescope which enables a relative astrometric precision of ~15 mas for…
We have obtained CCD photometry in the Washington system C,T1 filters for some 850,000 objects associated with 10 Galactic globular clusters and 2 old open clusters. These clusters have well-known metal abundances, spanning a metallicity…
The first results are presented of a four-year program dedicated to the CCD observations of Cepheids in the nearby galaxy IC 1613. Since the program was carried out with a relatively small telescope, the Dutch 0.9 m at ESO-La Silla, the…
Deriving atmospheric parameters of a large sample of stars is of vital importance to understand the formation and evolution of the Milky Way. Photometric surveys, especially those with near-ultraviolet filters, can offer accurate…
We present a means of characterizing and removing internal reflections between the CCD and other optical surfaces in an astronomical camera. The stellar reflections appear as out-of-focus images and are not necessarily axisymmetric about…
Beating the Earth's day-night cycle is mandatory for long and continuous time-series photometry and had been achieved with either large ground-based networks of observatories at different geographic longitudes or when conducted from space.…
An optimal maximum-likelihood technique for computing point-source image centroids from many, slightly offset, CCD frames is presented. The method is especially useful for measuring stellar proper motions from data taken with the Wide Field…
Long baseline interferometry is now able to resolve the pulsational change of the angular diameter of a significant number of Cepheids in the solar neighborhood. This allows the application of a new version of the Baade-Wesselink (BW)…