Distributions of count for all of the unmasked pixels in the whole frame (global; left panel) and in the local vicinity region around the galaxy (local; right panel). This local vicinity region is defined as the image area between the boundaries of two square boxes sized 250 × 250 pixels and 501 × 501 pixels from the galactic center, respectively. The solid black curves represent distributions for the sky-subtracted frame by our piecewise row-by-row and column-by-column fitting method, and for a further comparison, the dashed gray curves are for the frame without our accurate sky background subtraction but only with the simple global or local mean value subtraction for all unmasked pixels of the whole frame and of the local region.