Radiometric Calibration and SNR Calculation of a SWIR Imaging Telescope


Yilmaz O., Turk F., Selimoglu O.

2nd International Congress on Advances in Applied Physics and Materials Science (APMAS), Antalya, Türkiye, 26 - 29 Nisan 2012, cilt.1476, ss.365-369 identifier identifier

  • Cilt numarası: 1476
  • Doi Numarası: 10.1063/1.4751629
  • Basıldığı Şehir: Antalya
  • Basıldığı Ülke: Türkiye
  • Sayfa Sayıları: ss.365-369

Özet

Radiometric calibration of an imaging telescope is usually made using a uniform illumination sphere in a laboratory. In this study, we used the open-sky images taken during bright day conditions to calibrate our telescope. We found a dark signal offset value and a linear response coefficient value for each pixel by using three different algorithms. Then we applied these coefficients to the taken images, and considerably lowered the image non-uniformity. Calibration can be repeated during the operation of telescope with an object that has better uniformity than open-sky. Also SNR (Signal to Noise Ratio) of each pixel was calculated from the open-sky images using the temporal mean and standard deviations. It is found that SNR is greater than 80 for all pixels even at low light levels.