1 Institute of Information Technologies at Bulgarian Academy of Science (IIT-BAS)

1. a presentation by Dimo T. Dimov1 (dtdim@iinf.bas.bg ) in collaboration with Milan Dimitrijevic2 (mdimitrijevic@aob.bg.ac.rs ) Image Processing Suggestions to Improvethe Astronomical Multiexposure Wide field Plates Method 1Institute of Information Technologies at Bulgarian Academy of Science (IIT-BAS) 2Astronomical Observatory, Belgrade 8th Serbian-Bulgarian Astronomical Conference May 08-12, 2012, Leskovac, Serbia

2. Acknowledgements This work was supported by following grant of the Institute of Information Technologies (IIT) at Bulgarian Academy of Sciences (BAS): Grant # DO-02-275/2008 of the National Science Fund at Bulgarian Ministry of Education & Science.

3. Contents 1. Introduction 2. Proposed Method Description - Preliminary notes - The method’s idea - Formal description of the method - Extended interpretations - The algorithm proposed Experiments and Discussion 4. Conclusion

4. References • Aniol, R., H.W. Duerbeck, W.C. Seitter, M.K. Tsvetkov, An automatic search for flare stars in southern stellar aggregates of different ages, In L.V. Mirzoyan, B.R. Pettersen and M.K. Tsvetkov (Eds.), Flare Stars in Star Clusters, Associations and Solar Vicinity, IAU Symp. 137, Kluwer Acad. Publish., Dordrecht-Boston-London, 1990, pp. 85-94. • Winterberg, J., M. Nolte, W.C. Seitter, H.W. Duerbeck, M.K. Tsvetkov, K.P. Tsvetkova, “Flares and Flashes”, In J. Greiner, H.W. Duerbeck and R.E. Gershberg (Eds.), Proc. IAU Coll. 151, Springer Verlag, Berlin, 1995, p. 119. • Dimov, D., K. Tsvetkova, M. Tsvetkov, A. Kolev, O. Kounchev, Hough Transform Approach to Flare Stars Identification in Multi-Exposure Plates Images, Serdica J. of Computing(in a special issue on Astroinformatics) (to appear 2012) • Tsvetkov, M. K, K. Y. Stavrev, K. P. Tsvetkova, E. H. Semkov, A. S. Mutafov, and M. E. Michailov, The Wide-Field Plate Database: Present Status and Future Development, Baltic Astronomy, vol. 6, 271-274, 1997. • Dimov, D., A. Dimov, Data Driven Approach to Binarization of Astronomical Images, In: Proceedings of CompSysTech’10, June 17-18, 2010, Sofia, Bulgaria, Mini-Symposium on Astroinformatics, in 2010 - ACM International Conf. Proceeding Series, Vol. 471, ACM PRESS, NY, USA, ISBN 978-1-4503-0243-2, pp. 478-484. • Bertin, E., and S. Arnouts, SExtractor: Software for source extraction, Astronomy & Astrophysics Supplement Series, 117, (1996), 393-404.

5. An original image of “stellar chains” scanned from an archive photo plate in the Pleiades area The original wide field plate was produced using the Multi Exposure Wide Field Plates Method well known from astronomy practice of last century

6. A small part of the original “stellar chains” image, zoomed. It is well visible many chains overlap each other. And the question is: Are there any better choices for the chains params (chains’ direction and distances among components)

16. Optimal chains: - Slope =163 - Basic distance = 11/1680 - Overlapping = 5 % Chains of the archive plate: - Slope =3 - Basic distance = 6/1680 - Overlapping = 29 %

17. Discussion & Conclusions Discussion ? (about the method proposed considered as): • A post processing tool to evaluate the quality of the images of archival wide field plates with stellar chains  • A pre processing tool before the real usage of the MultiExposure (wide field) Plate Method (MEPM); it would make sense if you decide the CCD/LCD Astronomy (coming to replace the photography Astronomy) will be able and/or will have a need to rehabilitate the MEPM 

18. Thank You ! (for your interest and questions  )

19. Extra slides