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Integration time

For standard observations, where the object does not saturate the detector within the shortest integration time of the normal mode (400 ms), this normal mode should be used. For brighter objects, the integrated shutter allows integration times down to 20 ms. Figures 3.3 to 3.5 give a rough estimate of the longest integration time for a point source of given brightness. Because the image correction by the adaptive optics is depending on the seeing conditions, the maximum integration can vary by a factor of about two.

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Figure 3.3:   Maximum integration time for given brightness of an object observed in J-band

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Figure 3.4:   Maximum integration time for given brightness of an object observed in H-band

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Figure 3.5:   Maximum integration time for given brightness of an object observed in K-band



Frank Eisenhauer
Wed Apr 23 16:00:15 MDT 1997