1 / 28

Tangra – a new light measurement tool

Tangra – a new light measurement tool. Hristo Pavlov 4-th Trans Tasman Symposium on Occultations 5 April 2010, Canberra. A brief history of the project. Started as project for Astrometry Significant learning for me, read many papers on the topics of Photometry and Astrometry

zev
Download Presentation

Tangra – a new light measurement tool

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Tangra – a new light measurement tool Hristo Pavlov 4-th Trans Tasman Symposium on Occultations 5 April 2010, Canberra

  2. A brief history of the project Started as project for Astrometry Significant learning for me, read many papers on the topics of Photometry and Astrometry Shifted the main focus from astrometry to asteroid occultation measurements First line of code written in April 2009 In closed beta testing since January 2010 Planned release date as public beta – May 2010

  3. Why a new tool? Improved tracking Easier to reduce light curves by new users and more control for advanced users Ability to save and send a small in size light curve file that can be used by others to do additional reductions More ways to do photometry Ability to correct for Flats and Darks

  4. Learning – type of articles Image Calibration (Darks & Flats) Digital Filters Photometry – algorithms Photometry – standard system as filters Photometry - variable star methodology Astrometry Spacecraft Star Orientation – lost in space algorithms Packages for stellar photometry CCD and Video camera documentation

  5. Learning – specific publications Stetson. P., 1986, "DAPHOT: A computer program for crowded-field stellar photometry", http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=1987PASP...99..191S&db_key=AST Stetson. P., 1989, "The techniques of least squares and stellar photometry with CCDs", http://nedwww.ipac.caltech.edu/level5/Stetson/Stetson4_2.html Mighell, K., 1999, "Algorithms for CCD Stellar Photometry", http://www.adass.org/adass/proceedings/adass98/reprints/mighellkj.pdf Fadeyev, V., 2004, "PSF Photometry Lecture", http://panisse.lbl.gov/snphot/lec8_vitaliy_PSF_fit.pdf

  6. Prototype April – September 2009: Built a prototype to test the photometry and astrometry algorithms that are going to be used June – July 2009: Acquired and reported astrometry of bright asteroids and comets using the prototype to test the astrometry precision (~ 0.3”) October 2009: Did tests of the photometric algorithms with real star fields. Published the results on my web site at: http://www.hristopavlov.net/Articles/VideoPhotometry.html

  7. Demo - Astrometry

  8. Tangra Developed between November 2009 – April 2010 Used code from the prototype Rewrite of the tracking to add significant improvements In closed beta testing since January 2010

  9. Demo – simple light curve reduction DEMO1 - 2000AJ55 (17h 56m 36s -26d55'42'').AVI 12:12:35 – 12:13:05

  10. Demo – windy video DEMO2 - REC_049.AVI 9:11:08 – 9:12:08

  11. Demo – manually positioned aperture DEMO3 - DEMO3 - 071231_Nealley 41m25s.AVI 10:41:18 – 10:41:31

  12. Demo – single drift-through star

  13. Demo - .lc file without the video DEMO5 - Dione.lc

  14. Demo – software integration

  15. Questions ?

More Related