docs: def get_qpimage_raw(self, idx=0):
          """Return QPImage without background correction"""
          # Load experimental data
          with SingleTifHolo._get_tif(self.path) as tf:
              holo = tf.pages[0].asarray()
          meta_data = copy.copy(self.meta_data)
          qpi = qpimage.QPImage(data=(holo),
                                which_data="hologram",
                                meta_data=meta_data,
                                holo_kw=self.holo_kw,
                                h5dtype=self.as_type)
          # set identifier
          qpi["identifier"] = self.get_identifier()
          qpi["time"] = self.get_time()
          return qpi