Panoramic photo of the leaf
<a rel="nofollow" class="external text" href="https://creativecommons.net/meetthegimp/">Rolf</a>
CC BY-SA 3.0
<a rel="nofollow" class="external free" href="http://blog.meetthegimp.org/episode-4-a-ship-in-the-fog-2-correcting-colours/">http://blog.meetthegimp.org/episode-4-a-ship-in-the-fog-2-correcting-colours/</a>