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Asteroid images identification and crea- tion the positional catalogs based on digitized photograph- ic observations of previous years were continued. Namely, the cooperation between Ukrainian Virtual Observatory (UkrVO) and the Institute of Astrophysics of the Academy of Sciences of Tajikistan make it possible to expand this work by involving numerous additional archives of digitized observations and processing services and thus obtaining new original data about the Universe. The Dushanbe part of the Northern Sky Survey (FON project) is represented by about 1570 photographic plates obtained in 1985-1992 on the Zeiss-400 astrograph at the Hissar Astronomical Observatory of the Institute of As- trophysics of the Academy of Sciences of Tajikistan. At present, their digitization and further scan processing con- tinue until the final product is obtained in the form of a catalog of equatorial coordinates and stellar magnitudes for all registered objects on the plates. The equatorial co- ordinates α, δ of all objects on the plates were obtained in the Tycho-2 reference system at the epoch of exposure of each plate. Photometry of stars for the plates was carried out based on the principles implemented in the processing of the plates of the FON project using photoelectric meas- urements of stars to construct the characteristic curves of the plates. Photographic B-magnitudes of objects were calibrated with photoelectric standards. In parallel with solving the main task of the project to cre- ate a catalog of stars and galaxies, we analyzed the results of processing the plates to search for images of asteroids and comets and create a catalog of their coordinates and values. About 300 positions of asteroids and comets were obtained with visual magnitudes from 7 to 16.5. All positions of the asteroids were compared with the ephemeris. A preliminary analysis of the O-C differences and their comparison with similar results obtained from the digitized observations of the Kyiv and Kitab parts of the FON project are conducted.

In total, about 4,500 asteroid po-sitions were determined from photographic observations conducted at the MAO NAS of Ukraine in 1952-1996. These are the early positions of the selected minor planets, mostly bright, the observations of which were initiated by the founders of the ORBITA observational program and were made in 1952-1986. The second later positions of asteroids obtained from digitized plates from photographic observations of the Northern Sky Survey project in 1981-1996. Using digital plate processing technologies, 2292 asteroid positions were obtained, the images of which were fixed during observations and identified during processing.The new star catalog Gaia DR2 was used to study changes in determining the accuracy of equatorial coordinates for various faint objects on plates. For several 8 plates with images of Pluto comets and faint asteroids of particular interest due to the lack of observations in the past, new complete processing of scans of these plates was performed. The Gaia DR2 was used as a reference catalog. The asteroid positions from early observations of 1952- 1986 were determined in accordance with classical linear reduction algorithms. These are 1651 positions of minor planets determined in the PPM catalog system and obtained from observations with the Double Wide-Angle Astrograph. The remaining 591 positions were determined in the systems of old reference catalogs of stars Yale, SAO, AGK3, and obtained from observations with the Double Long-Focus Astrograph. It was for these positions that the calibration with the Gaia catalog was performed. The data on the positions of minor planets digitized from publications and additional data on their reference systems deposited in previous years at VINITI (now VINITI Database RAS) were used. Comparison with JPL ephemeris was performed both for new determinations of asteroid coordinates with the Gaia catalog, and for past determinations obtained in systems of other reference catalogs.

The UkrVO Joint Digital Archive of astro- plates and the newest digitized data processing services al- lowed us to form a new approach for the creation of catalogs of astrometric and photometric characteristics of the Solar System bodies. Given this, the main goal of this approach was not only to complete the processing with the best possi- ble accuracy of high-quality and unprocessed earlier photo- graphic observations of the Solar System bodies but also to find new original data from these observations. As a result, more than 6,500 new astrometric positions and stellar magnitudes of asteroids, and 3,036 positions of outer planets (Pluto, Uranus, Neptune, Saturn, Jupiter) and their satellites have been determined. Most of the posi- tions obtained from observations of large stellar surveys of the northern sky FON (Kyiv and Kitab parts) and other surveys (MEGA, Equatorial Catalog). The number of new obtained positions of asteroids is comparable to the total number of all positions of aster- oids obtained at the Main Astronomical Observatory of the NAS of Ukraine in 1949-1996. The accuracy of new positions is higher than in traditional determinations from photographic observations, but it cannot be comparable to the accuracy of modern CCD observations. Contrary to traditional classic definitions, digitized im- ages of plates have produced a large number of faint aster- oids down to 17.5 magnitudes, which were discovered in the early 21st century. For some of them, observations are either completely absent or not enough over the certain time interval preceding the moments of their official discoveries. These data can be obtained from photographic observations only. Based on our observations, about 300 such asteroids were found. The collection of missing data on positions over certain time intervals and their analysis can be useful not only for modern ephemeris calculations but also for studying the evolution of asteroid orbits over time. The cooperation between UkrVO and the observatory in Baldone of the University in Latvia, astronomical and astro- physical institutes of Uzbekistan and Tajikistan make it pos- sible to expand this work by involving numerous additional archives of digitized observations and processing services and thus obtaining new original data about the Universe.

The plan of the photographic survey of the northern sky (FON) was proposed in 1976 in Golosiiv ob- servatory (now MAO NAS of Ukraine) by I. Kolchinsky and A. Onegina. The final project of the Compiled FONAC catalog (FON Astrographic Catalog) is based on the digital data of photographic plates exposed at four observatories. They are MAO NAS of Ukraine (Kyiv, Ukraine), Kitab astronomical observatory (Tashkent, Uzbekistan), Hissar astronomical observatory (Dushanbe, Tajikistan), and Bal- done observatory (Latvia)). The total amount of plates is 5700. The result is expected to be the catalog of positions and B-magnitudes of stars covered the declination area from -20 to 90 degrees. The estimated mean epoch of the catalog is ~1987. The limiting B-magnitude is ~17.5 m . The reference system for positions is Tycho-2. B-magnitudes are being obtained in the system of photoelectric standards. The resulted data of photometric reduction are corrected for the photometric color equation in B magnitudes. The com- plement for the photometric content of the catalog is U and V magnitudes of stars being obtained from the processing of 5400 plates from the glass collection of 1.2 m Schmidt telescope in Baldone. Photometric data of bright stars with V < 8.5 m U, B,V magnitudes cannot be obtained from pho- tographic material, so those objects will gain photometric data from photoelectric catalogs. The catalog will be com- plemented with proper motions from GAIA.

Observations of 20 open clusters at the Maidanak Observatory were performed using the Zeiss-1000 telescope in the winter of 2018. As the light receiver, a CCD camera Apogee Alta U9000 (3K x 3K, FOV 19.5'x19.5') was used. All observations were performed using BVRI light filters. The exposure time, depending on the filter was from 60 to 150 seconds. Due to the instability of the telescope, images of the stars are slightly elongated. For each observation night, calibration images were obtained. Astrometric processing was carried out after filtering hot pixels. For testing purposes, we used two methods of reduction: by the Astrometrica program and the author's set of programs with primary processing in the MIDAS environment. The reduction of 280 frames was performed using a polynomial of the third degree. As reference stars in different processing options, the Tycho2, UCAC4 and Gaia DR2 catalogs were used. Due to the small field and the small number of reference stars, the processing in Tycho2 showed the worst result. The results obtained by author programs with reference catalogs UCAC4 and Gaia, showed good convergence. Integrated catalog of 18 thousand stars upto 18.5m was obtained. The accuracy of the catalog is σRA=0.011" and σDEC=0.013", the accuracy of single observation on RA (0.030 - 0.032)" and DEC (0.035 - 0.037)". At the same time, the accuracy of intraframe processing with the Gaia reference catalog turned out to be 2-3 times better than the analogous one with the UCAC4 catalog. The accuracy of processing elongated star images by the Astrometrica program is on the average 3-4 times worse than by the author's programs. Also a systematic dependence of the pixel scale on the using filter was found. Based on the results of the test photometric processing of NGC869 cluster a photometric estimate of the accuracy of the observations was obtained. The internal errors of one measurement of the stellar magnitude in the instrumental system bvr have the values σbvr = (0.03-0.05)m. After the reduction of instrumental stellar magnitudes to the Johnson BVR system, the errors of one measurement are σBVR = (0.05-0.08)m. The processing of observations showed the possibility of carrying out differential observations on the telescope Zeiss-1000 with an accuracy of one observation, not worse than 0.04", and near 0.02'' after improving telescope management.

The comparison results of three catalogues (FON-KIEV, FON-KITAB and FON-DUSHANBE) were received as result of work of the FON project and presented in the paper. The data of zero zone (from -2 to 2 degrees of declination) from the mentioned catalogues was used during the research. The number of common objects after cross-match of catalogues with a circular search window equals to 1.5 arc seconds was more than 500 thousands. The estimation of random accuracy of stars positions from the mentioned catalogues was performed by the Wielen method. Final dispersions were calculated for every sub-range of magnitudes. The stars with individual differences of position and magnitude that exceed three standard deviations were rejected. The data from catalogues РМА was used for estimation of the systematic errors. It is obvious that the internal estimates of position accuracy of stars in the compared catalogues are low in one or all catalogues, and additional research is required. Analysis of the behavior of the systematic differences and standard deviations of the stellar positions of these catalogues have shown that there are a big values reaching 1 arcsec only in small sky regions. However, the internal accuracy that presented in catalogues is well matched with the systematic differences and standard deviations in the other sky regions. Astrometry, astrometry-catalogue, data analysis.

Photographic observations of XX century contained numerous and varied information about all objects and events of the Universe fixed on the astronegatives. The original and interesting observations of small bodies of the Solar system in previous years can be selected and used for various scientific tasks. Existing databases and online services can help make such selection easily and quickly. The observations of chronologically earlier oppositions, photometric evaluation of brightness for long periods of time allow refining the orbits of asteroids and identifying various non-stationarities. Photographic observations of the Northern Sky Survey project were used for global search for small bodies of Solar system. About 2,000 photographic plates of Kitab part of the Northern Sky Survey project were made using Double Wide Angle Astrograph at the Kitab observatory, Uzbekistan during 1981-1989. Early, using that digitized observations the catalogue of equatorial coordinates and stellar magnitudes for 13 413 268 stars and galaxies up B≤17.5m was composed. At present, we analyzed all processing results for the search of asteroids and compilation of the catalogue of equatorial coordinates and stellar magnitudes of them. As a result more than 4,500 asteroids and comets with visual magnitude from 7m.7 to 17m.5 were identified now. All positions of asteroids were compared with ephemeris. A comparative analysis of O-C differences was carried out. New and interesting is that the moments of discovery of some identified asteroids much later than their moments of observation. In addition, some of them are the earliest observations of these asteroids in the world among all known observations. More than 915 observations of such asteroids have been found on the plates of Kitab part of the FON project.

The paper presents the first results of processing of photographic observations of SS bodies based on materials from the collection of plates of the Ulug Bek Astronomical Institute of theAcademyofSciencesof theRepublicofUzbekistan(AI ASRUz). The glass archive of the AI AI ASRUz has about 15 thousand photographic plates with images of various space objects. In this paper, we discuss the first results of processing of major planets’ photographic observations inUzbekistanusing the new technique. The observations were carried out on two astrographs –Tashkentnormal astrograph (TNA, D/F=330/3438) and Kitab Double Zeiss astrograph (DAZ, D/F=400/3000) in 1895-2004. Currently, in AI the work runs to streamline the archive and create a database of observations in a single xls-format. The number of photographic plates with images of major planets obtained on two telescopes is more than 300 negatives. In 2017, together with MAO NAS ofUkraine, the processing of these photographic observations using the new methodology was started. The plate digitization is performed on the flat-bed 10000XL in 1200dpi mode. Positions and photometric estimations in B-color of all registered on the plate objects are obtained using the software proposed and developed in MAO NAS of Ukrainerunning in LINUX/MIDAS/ROMAFOT environment. The search for major planets and their satellites among the whole set of plate objects and the comparison of their observed and predicted positions is carried out online with the help of internet-service (http://lnfm1.sai.msu.ru/neb/nss/nssephmr.htm). Up to date, the small part of the plate collection is treated, namely 23 negatives with images of Uranus, Neptune, Pluto and Saturn’s satellites, obtained on the Kitab DAZ astrograph. 16 negatives with 19 exposures gave the best results with (О-С) in the range ±1.5″. In total, we obtained 47 astrometric positions of the objects of interest in the wide interval of brightness’s (8m ±16m). The internal positional accuracy of the catalog in the Tycho-2 reference system is σαδ= 0.08″–0.13″, the photometric error of B-magnitudes is estimated as σB = 0.2m.

We have initiated the search of asteroids and comets on the basis of the processing digital images of plates obtained in the framework of FON project (the photographic survey of the northern hemisphere), Dushanbe section of the observational program. The result is the catalog of positions of the Solar System minor bodies. Observations were obtained in 1985-1992 at the Gissar Astronomical observatory of TajAPHI (Institute of Astrophysics of the Academy of Sciences of Tajikistan) on the Zeiss-400 astrograph (Marsden’s code 190, D/F=400/2000 mm). The plate collection includes around 1570 negatives covered the northern hemisphere from – 8° to + 90°. The plate digitization has started in 2017 after the commercial scanner Microtek ScanMaker 1000XL Plus was provided. The scanner was previously tested for systematic errors and proved for suitability for digitizing photographic plates. The joint research of MAO NAS of Ukraine and Gissar observatory on Dushanbe glass collection reduction has started in 2017. The astrometric reduction of digitized plates is conducted using the software developed in MAO NAS of Ukraine running in the LINUX/MIDAS/ROMAPHOT complex. To the current moment, 10% of the collection (171 plates) has been processed. For each fixed object we obtain positions in the TYCHO2 reference system. For stars in the magnitude range 5m-17m positional errors were estimated as ±0.36 arcsec, and B-magnitudes’ errors were found ± 0.12m . Stars and galaxies are not the only objects registered on the plates. During the observations, such objects as comets and asteroid could occasionally get on the picture. Here, we present the first results of the search for such objects on the FON photographic plates. The search and the evaluation of the convergence of minor bodies’ observed positions with the theoretic predictions are carried out online by jpl ephemerid service ( https://ssd.jpl.nasa.gov/sbfind).

Observations of open clusters at the Re- search Institute “Mykolaiv Astronomical Observatory” (RI MAO) were performed using the KT-50 telescope (D=500mm, F=3000mm) in 2011 – 2018. As the light re- ceiver, a CCD camera Apogee Alta U9000 (3K x 3K, FOV 42.6' x 42.6') in short drift scan mode was used. In short drift scan mode each observation consisted of several CCD frames with partial overlap in right ascension. All observa- tions were performed using R light filter. The exposure time was 20 seconds for all frames. All previous astromet- ric processing was carried out by the Astrometrica program and UCAC4 reference catalog. Using this data we received two catalogs of positions of 4.2 million stars (J2013.6) and 3.3 million starts (J2017.3) in the vicinity of open clusters with accuracy (0.03-0.07)". Unfortunately, current version of Astrometrica program have problem with data reduction with Gaia reference catalog in areas with big star density, like vicinity of open clusters near the plane of the Galaxy. At this article, we compared our old results with the new one for several open clusters which carried out with the author's set of programs with primary processing in the MIDAS environment. As reference stars the Tycho2, UCAC4 and Gaia DR2 catalogs were used. The reduction of 548 frames was performed using a polynomial of the third degree. The results obtained by author programs with reference catalogs UCAC4 and Gaia, showed good con- vergence. Several catalogs of positions of stars up to 17.5 m was obtained. The accuracy of the catalogs is σ RA =0.027" and σ Dec =0.033" for Gaia reference catalog and σ RA =0.032" and σ Dec =0.036" for UCAC4 reference catalog. At the same time, the accuracy of intraframe processing with the Gaia reference catalog turned out to be near 2 times better than the analogous one with the UCAC4 catalog. The compari- son showed the possibility of receiving more good results with Gaia reference catalog.

The arrivals of the new more accuracy reference catalogues and also development of new meth- ods and approaches for reduction astrometric data give the new life for photographic plates archives. Gaia DR2 is not only a giant step in the astrometric accuracy allowing to measure new objects also provides plates archives ob- served in the past with modern accuracy. In this work we present the first results of astrometric reduction in the sys- tem of Gaia DR2 for some photographic plates that were obtained by UK Schmidt telescope (UKST) and digitized by the SuperCOSMOS scanning machine. The UKST is a classical Schmidt with the following parameters: mirror diameter 1.83m; focal length 3.07m; photographic plate size 356mm square, covering 6.4 x 6.4 degrees of sky; plate scale 67.12 arcsec/mm. To date the UKST has taken over 17,000 plates, the plates are stored in the Plate Li- brary at the Royal Observatory, Edinburgh. The photo- graphic plates are digitized to 15 bits (32768 grey levels) with a resolution of 10 microns (0.67 arcsec)/pixel). Each digitized Schmidt plate has size 32256x32256 pixels and produces about 2 Gbyte pixel data .. We are making new reduction of photographic plates that allowing to provide valuable data for future researches in astrometry as well as in astrophysics. The obtained astrometric and photometric data from photographic plates were compared with same one from modern catalogues.

Catalogue of 13.4 million stars down to 17.5m was obtained in 2017 by using plates from the Kitab Observatory of Ulugh Beg Astronomical Institute (UBAI) of the Uzbek Academy of Sciences. Kitab's part of Photographic Sky Survey (Russian abbreviation is FON, in next contexts) project include more than 2600 photographic plates, exposed on the Double Astrograph of Zeiss (DAZ, D/F = 40/300, 69"/mm) from 1981 to 1996. Digitizationof these plates was made by using Epson Expression 10000XL scanner with the 1200 dpi resolution. Catalogue includes objects from the 1963 plates in declination zone between -20° and +2° for middle epoch 1984.97. The equatorial coordinates of objects were determined in the Tycho-2 reference system and the B-magnitudes in the system of the photoelectric standards. Five participants from Uzbekistan, Germany and Ukraine have taken part in the processing of the digitized images. The average internal accuracy of the catalogue for one observation are 0.23" and 0.15m for the equatorial coordinates and B-magnitudes respectively. For the stars brighter than 14m the errors are 0.09" and 0.05m respectively. The analysis of the catalogue and its comparison with the several astrometric catalogues was done.

We present the results of photographic observations’ processing of Saturn’s moons, Uranus, Neptune and their moons on the basis of MAO NAS of Ukrainephotographic observational archive. The analysis of the results is given. Observations were obtained using 4 telescopes: Double Long-Focus Astrograph (DLFA, D/F = 400/5500), Zeiss Double Astrograph (DAZ, D/F= 400/3000), Reflector Zeiss-600 (D/F= 600/7500), Wideangle Astrograph, (DWA, D/F= 400/2000). Observations were carried out during 1961 – 1990 (http://gua.db.ukrvo. org). Digitizing of plates has been done by EPSON EXPRESSION 10000XL (EE) flatbed scanner in 16-bit gray color range with resolution 1200dpi.( Andruk et al.: 2005, 2012; Golovnja et al.: 2010;. Protsyuk et al. 2014a, 2014b). The reduction of plates was made using the software developed in MAO NASU in the enhanced LINUX-MIDAS software kit. (Andruk V. et al.: 2016a, 2016b). Tycho2 was used as a reference system. The internal accuracy of the reduction for the first three instruments is ±0.08 – ±0.13 arcsec for both coordinates. For the wide angle astrograph DWA, RMS errors appeared 2 – 2.5 times higher. The total amount of processed plates with images of Saturn’s moons is 209 (511 frames), 33 plates contain the images of Uranus and U1,U2,U3,U4 moons, 29 plates have images of Neptune and N1 moon (Yizhakevych et al., 2015, 2016, 2017; Protsyuk et al., 2015). The online comparison of calculated positions of objects with IMCCE ephemeris data was made (http://lnfm1.sai.msu.ru/neb/nss/nssephmf.htm).

Almost 40-year history of FON project ended with the creation of the whole northern sky catalog of objects down to B ≤16.5m. The idea of 4-fold overlapping of the northern sky with 6 wide-field astrographs has not been realized in full. For historical reasons it has been transformed into the 2-fold overlapping observational program of MAO NAS ofUkraine, resulted in three versions of the multimillion catalog of positions, proper motions, and B-magnitudes of stars. The first version of 1.2 million stars had been finished before the 2000s and is based on the AC object list. The measurements of plates were made by automatic measuring complex PARSEC, specially developed for massive photographic reviews. As the input list was limited by AC objects, the most part of stars on the FON plates remained unmeasured. Principles of workflow organization of such works formed the basis for the further development of the project using the latest IT-technologies. For the creation of the second and the third versions of the catalog, the list of objects was obtained as a result of total digitizing of plates and their image processing. The final third version contains 19.5 million stars and galaxies with the maximum possible for the photographic astrometry accuracy. The collection of plates, obtained in other observatories – participants of the project, are partially safe and can be used for the same astrometric tasks.

In the framework of UkrVO national project the new methods of plate digital image processing are developed. The photographic material of the UkrVO Joint Digital Archive (JDA, http://194.44.35.19/vo-mao/DB/ archivespecial.php) is used for the solution of classic astrometric problem – positional and photometric determinations of objects registered on the plates including Saturn’s moons. The results of tested methods show that the positional RMS errors are better than ±150 mas for both coordinates and photometric ones are better than ±0.20m with the Tycho-2 catalogue as reference.

The two new catalogues for the zero zone of the FON project were created after the processing of two different collections of digitized photographic plates. The photographic plates were received at the DAZ and DWA telescopes of the Kitab observatory of the Republic of Uzbekistan (KO UAS) and of the Main astronomical observatory in Kyiv (MAO NASU) in the number of 90 and 120 plates, respectively. The digitization of these photographic plates in the frame of the Ukrainian Virtual Observatory project was performed by means of the Epson Expression 10000XL scanner with the scanning resolution of 1200 dpi. The coordinates of stars and galaxies for the both catalogues are determined in the system of the Tycho2 catalogue. The stellar magnitudes of all objects are done in B-magnitudes of the photoelectric standard system. The difference between the calculated and the reference positions is equal σαδ = ±0.06–0.07". The internal accuracy of the both catalogues for all objects is σ αδ = ±0.20", σB = ±0.18m and σ αδ = ±0.27", σ B = ±0.17m, respectively. We present the comparison of these both catalogues with each other and with the Tycho2, UCAC4 as well as PPMX catalogues and discuss the results.

The catalog of star positions and B-magnitudes for the circumpolar region (from 58° to 90° in declination) of Northern Sky Survey project has been created under the motto of the rational use of resources accumulated in UkrVO JDA (Joint Digital Archive) in MAO NASU. The total amount of processed plates is 477. Digitizing of astronegatives has been carried out using Microtek ScanMaker 9800XL TMA and Epson Expression 10000XL scanners, with the scanning mode – 1200 dpi, the linear size of the plates – 30x30 cm or 13000x13000 px. The catalog contains 1 975 967 stars and galaxies with B ≤ 16.5m for the epoch of 1985.28. The coordinates of stars and galaxies were obtained in the Tycho-2 reference system, and B-value in the system of photoelectric standards. The internal accuracy of the catalog for all the objects is σαδ = ± 0.23 "and σB = ± 0.12m (for stars in the range of B = 8m -14m errors are σαδ = ± 0.11" and σB = ± 0.06m). Convergence between the calculated and reference positions is σαδ = ± 0.06 "(for 171 124 stars from Tycho-2), and the convergence with photoelectric stellar B-magnitudes is σB = ± 0.15m (for 5130 stars). External accuracy from the comparison with UCAC-4 is σαδ = ± 0.33 "( 1 928 367 stars and galaxies were cross identified).

Photographic observations of XX century contained numerous and varied information about all objects and events of the Universe fixed on plates. The original and interesting observations of small bodies of the Solar system in previous years can be selected and used for various scientific tasks. Existing databases and online services can help make such selection easily and quickly. The observations of chronologically earlier ppositions, photometric evaluation of brightness for long periods of time allow refining the orbits of asteroids and identifying various non-stationaries. Photographic observations of Northern Sky Survey project and observations of clusters in UBVR bands were used for global search for small bodies of Solar system. Total we founded 2486 positions of asteroids and 13 positions of comets. All positions were compared with ephemeris. It was found that 80 positions of asteroids have a moment of observation preceding their discovery, and 19 of them are chronologically the earliest observations of these asteroids in the world.

TheUniversityofLatvia's Institute of astronomy possesses a collection of 22 thousand photographic plates taken by the1.2 mSchmidt telescope located at the Baldone observatory. Among others, there are 767 astronegatives in this collection obtained in 314 sky areas using the Johnson U-filter. The field of view of each negative covers 19 square degrees. The plate scale is 72”/mm. The digitizing of the UV-collection has started in June 2016 with EPSON EXPRESSION 10000XL flatbed scanner. The general aim of the digitizing is to obtain UV-magnitudes and positions of all objects registered on the plates. Up to date near a half of the UV-collection is digitized. 24 digitized MEGA program plates of the collection were used for the preliminary investigation of the quality of photographic material and scanner systematic behavior. The catalog of positions and UV-magnitudes of 68.784 stars and galaxies for 12 regions allows evaluating the expected accuracy of the whole observed material. The estimated accuracy for all objects is σαδ = ±0.28" and σU = ±0.20m for positions and brightness respectively. For the stars with U = 8m – 14m these errors are σαδ = ±0.11" and σU = ±0.09m. The convergence of coordinates with respect to the coordinates of the reference system Tycho2 is σαδ= ±0.06". The conformity with photoelectric Upe-magnitudes is ±0.13m.

Digital processing of photographic plates of star fields allows to determine with high accuracy the coordinates and stellar magnitudes for all registered objects on these plates. The processing results can be used for a broad search for images of small bodies of the Solar system and determination of their coordinates. From the observations of earlier epoch, we can extract information about the locations of these bodies well before discovering them. Modern approach to processing early photographic observations with new technologies can be an effective instrument for rediscovery of asteroids and correction their orbits. We analyzed the results of digital processing of observations of clusters in UBVR bands which were made on the 1.2-m Schmidt telescope of the Observatory of Institute of Astronomy ofUniversityofLatviain Baldone (code 069). As a result 87 images of minor planets from 9.8 to 17.1 stellar magnitude and 2 images of comets were identified on 152 plates for 1967-1996. The catalogue of positions and stellar magnitudes of the searching asteroids was compiled. Among them 12 observations of asteroids are the earliest of the world's known observations of these asteroids. All positions of asteroids were compared with the ephemeris JPL DE431. Analysis was carried out.

The results of GRB observations are being published in the GCN Circulars in real-time. To study all the objects in the sky areas around the GRBs we identified them on the digitized MAO Double Wide angle Astrograph (DWA) plates (D/F=40/200) within a circle with the radius of dozens of arcminutes. We selected only GRBs with the positional accuracy between ±0.3" and ±7.5" and the range of magnitudes between 14m and 20m. We used MIDAS/ROMAFOT package to obtain the catalogues of the faint objects in small areas in the GRBs vicinity. For the plates of DWA telescope the positional rms errors are ± 0.20" for RA and DEC, the photometric errors are ± 0.20m . All positions were obtained in Tycho-2 system.

In order to calibrate the images of astronomical photographic plates from the archive of UkrVO was created the compiled catalogue of photoelectric UBVR stellar magnitudes. It is based on: the Kornilov catalogue of 13586 WBVR stellar magnitudes (Kornilov at al., 1991), the Mermilliod catalogue of 68540 UBV stellar magnitudes (Mermilliod, 1991) and the Andruk catalogue of 1141 UBVR stellar magnitudes (Andruk at al.,1995). All original coordinates have the different epoch and equinox. We performed the cross reference of stars from these three catalogues with the Tycho2, UCAC4 and XPM catalogues and created a new photometric catalogue on the epoch and equinox of J2000.0.

The Pleiades Star Cluster (M45) is one of the most studied star clusters in the galaxy. At the same time as part of the Pleiades are many long-period variable stars, including flashing that need further study. Recent work on the processing of photographic images of the Pleiades obtained at different observatory revealed a number of star clusters with large variations in coordinates, the reason you want to understand. Collection of UkrVO unified digital archive contains a number of plates with images of the stars of the Pleiades obtained on different instruments. Processing of this material allows to test out standard programs for digital astronomical images processing. Also we will add information about variable stars and will improve the coordinates and proper motions of cluster stars. Selected material covers the period 1909 – 1999 years. The plates have different margins, scale, number of stars on images and obtained limiting magnitude. Exactly this diverse set of options lets you to be sure of results.