Stock photographs are everywhere — billboards, magazines, brochures, and websites. They can be found in viral memes and even political ads. Even Bliss by Charles O’Rear, the background for Windows XP — often called the most “recognizable” photograph in history — got its start on a stock photography website. Stock photographers often work without clear-cut assignments and with full creative control over their work. As a result, stock photography collections like the 500px collection on Getty Images are astonishingly diverse…