Figure 11. A 6-hour-long GLORIA pass after the the striped noise removal procedure was applied. The correction involves combining two filtered components of the image. One image contains the high-frequency (high-pass filter) component of every line without the noise. The other image contains the low-frequency background brightness (low-pass filter) of a broader swath image without the noise. The high-pass and low-pass images are then combined to recreate an image similar to the original, but without the noise. Compare this improved image with the previous image (fig. 10) (Twichell, 1988).