Second body for wildlife photography

Wait for the D7100 or D400 when they are released next spring.

You may also have to get your Sigma lens OS unit serviced by Sigma. Mine quit working good after about a year and I had to have it replaced (it did work somewhat, just not well). That could be part of your problem.

As for me, I tried the D7000 and sold it after a year because I did not like the AF. I am now using my D700 with TCs in the meantime and saving my pennies for the D400. The D700 is 12 MP and prints 11x14 just fine, even if I have used a TC.

So another option is to get a gently used D700 to tide you over until the D400 is released. Keep in mind that the D700 will continue to drop in price now that the D600 and D800 are out. I already had the D700 for low light and event work.

The D600 is a non-starter for me since it has the same crummy 39 pt AF as the D7000 (maybe marginally improved). I lived with that in the D7000 for a year and hated it. No way am I going backwards from my 51 pt AF that works so well in the D300/D300s/D700/D3.

And the D800 is too expensive and I do not like the 4fps limitation.

Good luck. There are a lot of us in the same situation.

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Catallaxy