Noise on image (very grainy)



The attached image was taken with Nikon D3s + Nikkor 300mm f4 + 1.4 TC,

Do you think the noise level is acceptable, given the fact that it was taken with D3s and only ISO 1600, f5.6, 1/500.

This camera is supoosed to be the best in high ISO, any explanation as to why would be appreciated.

Cheers

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http://www.flickr.com/photos/walidhassan/
Nikon D80, D300, D3s
18-135m,50 mm f1.8, 70-300mm VR, Sigma 150mm f2.8, Nikon 300mm f4 AF-S, Tamron 28-70 f2.8, Nikon 24-70 f2.8
SB600, Wireless Flash Trigger
slingshot 200 AW
Giotto tripod, Giotto ballhead
Manfrotto Monopod 680B
Cokin Filters
1.4TC