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7.4.3.7 Upper limit magnitude of image

As mentioned in Upper limit magnitude of each detection, the upper-limit magnitude will depend on the shape of each object’s footprint. Therefore we can measure a dataset’s upper-limit magnitude using standard shapes.

Traditionally a circular aperture of a fixed size (in arcseconds) has been used. For a full example of implementing this, see the respective section in the tutorial (Image surface brightness limit).