HUGSFiducial = measure_fiducial_lines(
    HUGSSub['F606W'].values,
    HUGSSub['F814W'].values,
    HUGSSub['F606W_RMS'].values,
    HUGSSub['F814W_RMS'].values,
    binSize='uniformCS',
    targetStat=100,
    mcruns=5,
    convexHullPoints=50,
    nPops=1)