As for questions concerned about battery life of a single ENEL15c in the Z8 ?
Well, a fully charged ENEL15c packs a fair charge with its rating of 2280 mAh, especially if we compare the bulkier 3300 ENEL18d, and it gets close to the earlier ENEL18 models, 2500 mAh
I get workable mileage out of the ENEL18c in the Z9.
The mileages remain to be tested, out in the wilds, but the Z8 grip appears to be essential for sustained video shooting. This is particularly as it allows Hot swopping of the A battery. Direct charging 1 or 2 batteries can also be useful, given that Nikon has yet to update (?!?) the MH25a charger into the PD universe. It's a few years trailing how the Mh-33 works so compactly with the ENEL18# batteries.
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