Example of a daily pB image acquired by Mauna Loa on August 30, 2008. Left panel: Original pB data in polar coordinates (heliocentric distance on the x axis, polar angle measured counter-clockwise from the polar north on the y axis). Left-middle panel: Polar coordinates of the pB fit. Right-middle panel: Relative difference between the original data and fitted data. Right panel: Resulting electron density in polar coordinates.