I have been following the reviews of the 200-500mm with great interest to see if it a superior alternative to Canon offerings. By coincidence, I was able to handle one yesterday and also TDP posted its image quality on the D3S.
http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=1035&Camera=614&Sample=0&FLI=3&API=0&LensComp=972&CameraComp=963&SampleComp=0&FLIComp=4&APIComp=1
Reviews so far have frequently raved about the sharpness of the 200-500mm but there is near unanimity that its AF is slow for BIF. However, the MTFs on ePhotozine are not remarkable and you have to stop down to f/8 - f/11 for best sharpness. One I reviewer decided to keep his Sigma 150-600mm S as it was significantly sharper and sell the 200-500mm.
The TDP tests show it has much poorer IQ than the 100-400mm on the 1Ds3, and the Canon with a 1.4x TC is still sharper. In addition, the 100-400mm II on the 7DII has better IQ than the 200-500mm on Nikon FF and with more effective reach. The Nikon at 2.4 kg is more than 700 g heavier than the Canon lens. So, I am not tempted to migrate to the D500 + 200-500mm.
http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=1035&Camera=614&Sample=0&FLI=3&API=0&LensComp=972&CameraComp=963&SampleComp=0&FLIComp=4&APIComp=1
Reviews so far have frequently raved about the sharpness of the 200-500mm but there is near unanimity that its AF is slow for BIF. However, the MTFs on ePhotozine are not remarkable and you have to stop down to f/8 - f/11 for best sharpness. One I reviewer decided to keep his Sigma 150-600mm S as it was significantly sharper and sell the 200-500mm.
The TDP tests show it has much poorer IQ than the 100-400mm on the 1Ds3, and the Canon with a 1.4x TC is still sharper. In addition, the 100-400mm II on the 7DII has better IQ than the 200-500mm on Nikon FF and with more effective reach. The Nikon at 2.4 kg is more than 700 g heavier than the Canon lens. So, I am not tempted to migrate to the D500 + 200-500mm.