I shoot with this type of battery grip. It’s great to be able to shoot all day and not worry about the batteries dying. However, when it’s dead, it’s dead. This hack is useful for people who don’t pay attention to how much ‘juice’ they have left. When the battery dies, you can just switch them and keep shooting. I know you could ditch the grip and keep an extra battery in your pocket, but the battery grip makes holding the camera much easier.
There is just one problem with that setup: Canon decided to design the battery grip in such a way that it drains bower from both batteries at a time while you’re shooting. On the one hand this means that you can take pictures for a longer period of time but on the other hands you’re still bummed when you run out of battery juice and have to dig through your backpack (you didn’t leave it at home or in the car, did you?) to load a fully charged battery.
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