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7.3.3 Wiggle Corrections

  Localized discontinuities (wiggles) in the spatial direction are also detectable in high-dispersion images for all three cameras. Corrections, similar to those developed in low dispersion for the long-wavelength cameras, have been derived which map out these distortions present in every order. The SWP wiggles demonstrate a time dependency in patchy areas on the camera surface. Therefore, two SWP correction templates have been derived: one for early-epoch (before 1988 January 02) images, the other for late-epoch (after 1990 January 02) data. Wiggle corrections are interpolated linearly for SWP high-dispersion images obtained between these two dates. The LWP and LWR cameras have only single-epoch correction templates. The wiggles among the SWP images correlate well enough that a mean-wiggle template removes at least half the amplitude of the excursions in an individual image. The wiggles present in long-wavelength images are not as well correlated.



Karen Levay
12/4/1997