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We report the flux and spectral variability of PG 1553 + 113 on intra-night (IDV) to short-term time-scales using BVRI data collected over 91 nights from 28 February to 8 November 2019 employing 10 optical telescopes: three in Bulgaria, two each in India and Serbia, and one each in Greece, Georgia, and Latvia. We monitored the blazar quasi-simultaneously for 16 nights in the V and R bands and 8 nights in the V, R, I bands and examined the light curves (LCs) for intra-day flux and colour variations using two powerful tests: the power-enhanced F-test and the nested ANOVA test. The source was found to be significantly (>99 per cent) variable in 4 nights out of 27 in R-band, 1 out of 16 in V-band, and 1 out of 6 nights in I-band. No temporal variations in the colours were observed on IDV time-scale. During the course of these observations the total variation in R-band was 0.89 mag observed. We also investigated the spectral energy distribution (SED) using B-, V-, R-, and I-band data. We found optical spectral indices in the range of 0.878 +/- 0.029 to 1.106 +/- 0.065 by fitting a power law (F-nu proportional to nu(-alpha)) to these SEDs of PG 1553 + 113. We found that the source follows a bluer-when-brighter trend on IDV time-scales. We discuss possible physical causes of the observed spectral variability., QC 20230320

The plan of the photographic survey of thenorthern sky (FON) was proposed in 1976 in Golosiiv ob-servatory (now MAO NAS of Ukraine) by I. Kolchinskyand A. Onegina. The final project of the Compiled FONACcatalog (FON Astrographic Catalog) is based on the digitaldata of photographic plates exposed at four observatories.They are MAO NAS of Ukraine (Kyiv, Ukraine), Kitabastronomical observatory (Tashkent, Uzbekistan), Hissarastronomical observatory (Dushanbe, Tajikistan), and Bal-done observatory (Latvia)). The total amount of plates is5700. The result is expected to be the catalog of positionsand B-magnitudes of stars covered the declination areafrom -20 to 90 degrees. The estimated mean epoch of thecatalog is ~1987. The limiting B-magnitude is ~17.5 m . Thereference system for positions is Tycho-2. B-magnitudesare being obtained in the system of photoelectric standards.The resulted data of photometric reduction are corrected forthe photometric color equation in B magnitudes. The com-plement for the photometric content of the catalog is U andV magnitudes of stars being obtained from the processingof 5400 plates from the glass collection of 1.2 m Schmidttelescope in Baldone. Photometric data of bright stars withV < 8.5 m U, B,V magnitudes cannot be obtained from pho-tographic material, so those objects will gain photometricdata from photoelectric catalogs. The catalog will be com-plemented with proper motions from GAIA., План фотозйомки північного неба(ФОН) був запропонований у 1976 році в Голосіївськійобсерваторії (нині МАО НАН України) І. Колчинськимта А. Онєгіною. Остаточний проект каталогу складено-го FONAC (FON Astrographic Catalog) ґрунтується нацифрових даних фотопластинок, експонованих у чоти-рьох обсерваторіях: МАО НАН України (Київ, Украї-на), Кітабська астрономічна обсерваторія (Ташкент,Узбекистан), Гіссарська астрономічна обсерваторія(Душанбе, Таджикистан) та Балдонська обсерваторія(Латвія). Загальна кількість пластинок – 5700. В резуль-таті повинен бути створений каталог положень і B-величин зірок, який охоплюватиме область неба від -20до 90 градусів DEC. Орієнтовна середня епоха каталогу– 1987 рік. Гранична В-величина становить ~ 17,5 m .Опорною системою є Tycho-2. В-величини визначають-ся у системі фотоелектричних стандартів. Отриманідані фотометричної редукції коригуються за фотомет-ричне рівняння кольору у величинах B. Доповненнямдля фотометричного вмісту каталогу є величини U та Vзірок, отримані при обробці 5400 пластинок 1,2 м теле-скопа Шмідта в Балдоне. Фотометричні дані яскравихзірок з величиною V <8,5 m U, B, V не можуть бути ви-значені з фотоматеріалу, тому ці об'єкти отримувати-муть фотометричні дані з фотоелектричних каталогів.Каталог буде доповнений власними рухами з GAIA.

The plate archive of the 1.2 m Baldone telescope (Latvia) has approximately 780 and 4660 astronegatives exposed in 1967-1993 in the U (ZU21 + UG1 filter plates) and V (A600N + ZS17 filter films) closed to Johnson system U and V passbands. Digitization of astronegatives is carried out using the Epson Expression 10000XL scanner, the scanning mode is 1200 or 2400 dpi, each field covers 19 square degrees of sky. The plates and films are scanned at the Baldone Observatory, processing of digitized scans is carried out by the observers in Baldone, at the Research Institute "Mykolaiv Astronomical Observatory" and at the Main Astronomical Observatory of the National Academy of Sciences of Ukraine. The Epson Expression 10000XL Scanner, along with the software developed, allows us to digitize and process the plates and receive coordinates and magnitudes of registered objects (with high, moderate and low brightness) with an internal error of no worse than 0.05 seconds of arc and 0.03 magnitude. The astrometric and photometric reduction of digitized astronegatives is done in the Tycho-2 reference system and U, V photoelectric system. At this report, we present first results of reduction of more than 2000 astronegatives. Data of U and V magnitudes of stars and galaxies will be used as the photometric addition to the FON project, without, the long-term series of U, V observations have an independent value for studying the variability of stars. Also, many plates included open clusters and will be used for investigation of their population and photometric parallaxes.