>Let's imagine you can get close enough to the croc with your >D700 and 300mm lens for it to cover 1000 pixels horizontally >in the frame. > >At that same distance, replacing the 300mm on the D700 with a >500mm would allow the same croc to cover about 1670 pixels. >On the other hand, by keeping the 300mm and replacing the D700 >with a D800, the croc would cover 1730 pixels, so purely in >terms of number of pixels you'd be slightly better off getting >a D800 than a 500mm.
Tks Brian, Actually I should study the math to get a better grip on this, Price for a 500 f4 in my country is around $10000, Not sure about D800 yet? Small birds are the real issue, they just fly away when you get too close Stealth may just be a lot more economical Regards, Gary