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+transmission.txt and ratio_order_2_over1.txt are made with the merge-efficiencies.py script here
+https://gitlab.in2p3.fr/llg/lsst-lpnhe-bench/-/tree/master/py/analysis/AuxTel-holograms
+combining two sets of transmission measurement of the holo-4-003 holograms performed on the optical test bench at LPNHE.
+The error bars come from the difference between the two runs.
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