def get_corrector_f(rinput, meta, ins, datamodel):
    """Corrector for intensity flat"""
    from emirdrp.processing.flatfield import FlatFieldCorrector
    flat_info = meta['master_flat']
    with rinput.master_flat.open() as hdul:
        _logger.info('loading intensity flat')
        _logger.debug('flat info: %s', flat_info)
        mflat = hdul[0].data
        # Check NaN and Ceros
        mask1 = mflat < 0
        mask2 = ~numpy.isfinite(mflat)
        if numpy.any(mask1):
            _logger.warning('flat has %d values below 0', mask1.sum())
        if numpy.any(mask2):
            _logger.warning('flat has %d NaN', mask2.sum())
        flat_corrector = FlatFieldCorrector(mflat,
                                            datamodel=datamodel,
                                            calibid=datamodel.get_imgid(hdul))

    return flat_corrector
Corrector for intensity flat