I use mine attached to a D700. Typical shooting conditions that I encounter are - low light, fast action of on-stage performances.

Which batteries (brand/technology) are you using to power the grip? Would be extremely helpful if you provide indicative number of shots under the following circumstances:

1) 8 fps engaged 50% of the time, 51 point AF with 3D tracking
2) Single shot engaged 100% of the time, normal single-point focus

I managed to half-drain (according to battery meter) new Duracell AAs after around 400 shots, so wondering if its a grip problem or should I use rechargeables in order to get longer life.

Also, does it matter that rechargeable cells provide 1.2 volts each while LR6 AAs e.g. Duracells/Energizers provide 1.5. Does that impact getting 8 fps vs not getting it?

Thanks!
Soumit
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