The apparent brightness of the stellar halo is higher to the right of the saturated columns. This is particularly obvious at the bottom of the image in Figure 4.3 which is a region in the shadow of the pyramid edge. This model only works on very highly saturated stellar images. This effect appears to be a signal which starts at a saturated pixel and decays over the next few rows, wrapping around as it does so. The signal is additive with each successive saturated pixel.
Jumps are obvious when the number of saturated columns changes.
The problem is a known characteristic of the amplifier electronics, and effort was made to minimize it during design. An exponential function fits the effect reasonably well. An appropriate algorithm creates an array to contain the signal model. When it encounters a saturated pixel, it adds an exponential function to the model array, beginning at that pixel. The halfwidth, h , and amplitude, A , appear to vary from frame to frame and must be determined on the image itself.