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Combining IDF files

IDF files for different exposures can be combined into a single one. This results in a higher Signal to Noise ratio, allowing a better computation of the background and the Y centroid. Thus it is recommanded to combine your exposures before extracting, especially if your target is faint.

The exposures to be combined should generally come from the same observation (or two observations of the same target in the same aperture that are close in time) , the same detector, and the same segment.


Bernard Godard 2004-11-04