I used both the Vellos and the Zeikos grip for the D7000. So far from
my own experience with both of these grips the aftermarket grips do
not talk with the body in relation to having both batteries installed.
(one in the grip and one in the body)

When you go into the D7000 menu and select which batt you want to use
first or let the camera decide the D7000 doesn’t recognize the batt
in the aftermarket grips AT ALL!!! ONLY!!!!! if you take the batt
out of the body then ONLY will the D7000 use the Batt in the grip.

Everything works perfectly with the Nikon grip.

Visit Current D90 Set-up.

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