DECAM DomeFlatFrame divided by pixel-to-pixel gain y=::4, x=::4

On the left side a section of the DomeFlatFrame for ccd DECAM_S05 is shown. On the right side the same DomeFlatFrame divided by the pixel-to-pixel gain is shown.
Both sides are part of one two-dimensional numpy array and are scaled in exactly the same way by matplotlib. The only difference between the left and right sides is the pixel-to-pixel gain. Although the right side looks like a smoothed version of a noisier left side, no smoothing has been applied.
The same pixel-to-pixel gain has been applied to all DECAM@BLANCO filters below.
For better inspection it is recommended to download the images and use a local application that can disable anti-aliasing. For example

feh --force-aliasing -F -Z -S filename exf-dome-DECAM_*.png