
Originally Posted by
Arthur Morris
It is worse than it seems on the surface. With the 800 alone and the Mark III, the equivalent focal length is 1040mm, or 20.8X magnification. With the 800 and the 50D, it would be 1280 effective at 25.6 magnification. And with the 800, the Mark III, and a 1.4X TC, the equivalent focal length is 1456mm, or 29.12X magnification.
Folks often say, "If I had that lens...." Then I have them put flash card in the camera and they go, "Can you help me find the bird in the viewfinder?" In addition, the longer the equivalent focal length the more perfect you have to be with your sharpness techniques. Anyone can use long effective focal lengths--getting sharp images is the big trick. Not to mention, after you find the bird and learn how to make them sharp you still have to get the right EXP and design a pleasing COMP.... You gotta love it!