photometry of SN1993J at Ouda

  BVIc-magnitudes of SN 1993J obtained at Ouda

  (new) local standard: Richmond star C
                      V=14.51, B=15.11, Ic=13.87
                      (average of WH20n & PP in de Vacouleurs' compilation)

    mid-UT    SN - starC    N band     SN mag     B-V
              mean  +/-                           V-Ic
 -----------------------------------  --------  -------
  931211.795  1.815 0.025   2 V         16.33
  931211.803  1.592 0.035   3 B         16.70    +0.37
  931211.810  2.491 0.044   3 Ic        16.36    +0.03
 -----------------------------------  --------  -------
  931212.805  1.808 0.015   7 V         16.32
  931212.855  1.600 0.019   7 B         16.71    +0.39
  931212.826  2.474 0.045   7 Ic        16.34    +0.02
 -----------------------------------  --------  -------
  940104.728  2.210 0.026   8 V         16.72
  940104.779  1.917 0.038   9 B         17.03    +0.31
  940104.748  2.914 0.031   8 Ic        16.78    +0.06
 -----------------------------------  --------  -------
  940107.718  2.206 0.020   6 V         16.72
  940107.740  2.029 0.033   6 B         17.14    +0.42
  940107.762  2.981 0.041   6 Ic        16.85    +0.13
 -----------------------------------  --------  -------

  (+/- = 1-sigma nominal standard error for an average)

  The magnitudes are systematically fainter than Leuschner 20" photometry
  by M. Richmond.  This difference may be due to different response
  between both instruments, different local comparisons, image sizes,
  and measuring algorithms.

Regards,
Taichi Kato