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Next: The 1515Å Artifact Up: 6.4.3 ITF Artifacts Previous: 6.4.3 ITF Artifacts Permanent Artifacts and Reseaux

The permanent ITF artifacts have been cataloged and both the artifacts and reseaux have been removed from the ITF images with a bi-linear interpolation scheme. The location of the specific pixels affected by either an artifact or reseau mark have been preserved in an ITF-dependent ``permanent blemish'' reference image. This image is used in the pipeline processing during the PHOTOM step to flag pixels in the science image whose location is coincident to those of the ITF blemishes. The $\nu$ flag values corresponding to permanent ITF artifacts and reseaux are -2048 and -4096, respectively. Because the ITF has been spatially interpolated in these regions, the accuracy of PHOTOM is somewhat degraded in the vicinity of the pertinent artifacts and reseaux.

Karen Levay