A cheap alternative to long lenses over 500mm are mirror lenses.  Cost effective, light, and extremely portable, mirror lenses have become popular with amature photographers who operate on a tight budget.  One drawback of mirror lenses are the unusual bokeh or blurry circles. 

Telephoto Zoom Lenses

Lens Price Image
Sigma 200-500mm f/2.8 $26,000
Tamron 200-500mm f/5-6.3 $1000

Mirror Lenses

Lens Price Image
Vivitar 650-1300mm f/8 $230
Pro Optic 500mm f/6.3 $160


A typical lens provides a smooth bokeh, usually a solid round circle.  Bokeh from mirror lenses provide a hollow circle, almost like a doughnut.  Compare the two images below.  Notice the top image has smooth colored circles while the botom image has a large group of "doughnuts."

White wine bokeh.jpg
18-55mm lens bokeh
Sigma mirror lens - white rod1 of 1.jpg
Mirror Lens Bokeh.
Community content is available under CC-BY-SA unless otherwise noted.