Curves show the incremental field differential refraction for three different instrument FOVs (φ = 0.5,1,2 deg), and three different fields (δ = −75, − 25, + 25 deg) observed from Paranal. All deviations are shown relative to the effect at HA = 0 h. The effect starts to become significant (≳0.1 arcsec) even for HA ~ 1 h for fields culminating to the north.
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