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5 Raw Image Registration (CROSS-CORR)


The NEWSIPS system relies upon an explicit determination of the registration between the raw science image and the raw space Intensity Transfer Function (ITF) to apply an accurate photometric correction (discussion of the ITF is deferred until Chapter 6). The image registration is derived using a linear cross-correlation algorithm with the fixed pattern found in all IUE raw images as the registration fiducial. In this context the fixed pattern is a manifestation of systematic variations in sensitivity from pixel-to-pixel over the entire image.


Karen Levay