The sequence above shows the setting Sun dipping toward the western horizon as observed from Veszprem, Hungary. As the Sun sinks lower, its color becomes more reddened because the path length of sunlight is increasing, resulting in the shorter wavelength colors of light (blues and greens) being preferentially scattered from our view. The longer wavelengths (reds, oranges, yellows) remain to color the Sun. Only if clouds or sufficient aerosols are present will the sky take on shades of red. In this case, exposures were selected to enhance the Sun, not the sky.
Note that the striped Sun in frame five is due to thin clouds near the horizon. Sunspots may be discerned in frames one, two and three (upper left quadrant). Be sure to protect your eyes when looking toward the Sun. Photos taken on April 18, 2011.