Form of the Photometric Equation

  r_std = -2.5log10(counts[ADU]/sec) - a_r - k_r*X - b_r*( (g-r)_std - 0.09) )

    r_std is the standard, or calibrated, magnitude of the star
    (g-r)_std is the standard, or calibrated, g-r color of the star
    a_g is the photometric zeropoint in g
    k_g is the first-order extinction in g
    b_g is the instrumental color term coefficient in g
    X is the airmass
    0.53 is a "fiducial" reference color for stars in g-r (based on SDSS experience)

    Note that there is a separate photometric zeropoint (a_i) and 
    instrumental color term coefficient (b_i) for each CCD.

NCSA Processing Results

Special Processing Results

  • RMS of the Solution: 0.015mag
  • psmtable.20121102.r.txt : ASCII file with Tabulated Values for zeropoints, color-term coefficients, and first-order extinction

Attached Files