def calc_dynamic_range_threshold(imax, dynamic_range_dr):
    """
    Calculates the dynamic range threshold
    imax (float): the maximum in the input image
    dynamic_range_dr (float): the dynamic range you want to calculate the threshold for
    returns (float): the dynamic range threshold
    """
    dynamic_range_threshold = imax / dynamic_range_dr
    return dynamic_range_threshold
