def scaled_exposure_time(self):
        """
        scaled "effective" exposure time of IID counts. This can be used by lenstronomy to estimate the Poisson errors
        keeping the assumption that the counts are IIDs (even if they are not).

        :return: scaled exposure time
        """
        if self._data_count_unit == 'ADU':
            exp_time = self.ccd_gain * self.exposure_time
        else:
            exp_time = self.exposure_time
        return exp_time