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Table 2

Root mean square thresholds (in %) for the different photometricity source distributions.

Sources Photometric Non-photometric

SkyProbe  <2.5  >3.5
SNIFS guide star  <2.5  >5
SNIFS photometry  <2.5  >4
SNIFS standard stars  <2.5  >4

Notes. For values intermediate between the photometric and non-photometric thresholds, a combination of indicators is used to ascertain the temporal stability of the atmospheric transmission.

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