Astronomical Video Reduction Software

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Hristo Pavlov

IOTA 2011, 17 June 2011

LiMovie Pros

Lunar OccultationsFresnel Diffraction ToolLunar Grazes and Mutual Events

ConsBasic tracking “Blind” measurements May need other software (AviSynth)Manual update

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Tangra Pros

Review measurements frame by frameCan open almost all videos directlyWorkflow. Improved trackingRange of measurement methodsPre-processing and software integration

ConsNo Lunar Occultations support No Mutual Events support

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Tangra - Photometric Methods Papers

Mighell, K., 1999, "Algorithms for CCD Stellar Photometry“ Stetson. P., 1986, "DAPHOT: A computer program for crowded-field

stellar photometry", Naylor, T. 1998, An Optimal Extraction for Imaging Photometry

Aperture Photometry

PSF Photometry

Numerical

Analytical

Optimal Extraction

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Low Pass Filter – LP

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Low Pass Difference Filter – LPD

Demo

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Video Astrometry

Accuracy ~ 0.2 pixels (~ 0.3 arcsec) Fast moving objects Measuring multiple frames Scientific value

Near Earth Asteroids (NEA)Comets

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Tangra Astrometry - Requirements Star catalogue – UCAC2, UCAC3 or

NOMAD Calibration

Take video of a known fieldManually identify three stars

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Astrometry of NEA

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Astrometry - NEA

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Astrometry - Comet

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Astrometry – Comet

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Questions?

http://www.hristopavlov.net/Tangra/

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