Short answer: one NB-13L in a G7X Mark III runs about 60-80 minutes of continuous 1080p, or about 35-55 minutes of 4K. Two packs cover a half day of shooting, three to four a full day out. Canon’s own CIPA rating is about 55 minutes of video and roughly 90 minutes of continuous recording; understanding why those two figures differ is how you work out how many packs you need.
The CIPA 55 minutes is measured in a loop of powering on, zooming, powering off and starting again, so it includes handling and standby. The 90 minutes is the ideal-condition continuous total. Real shooting lands between the two, depending on how you work.
Turning the official numbers into plain terms
| Way of shooting | Usable time per pack | Notes |
|---|---|---|
| CIPA loop test | About 55 minutes | Includes power cycling, zooming and review — close to casual use |
| Continuous 1080p | About 60-80 minutes | Screen on, Wi-Fi off |
| Continuous 4K | About 35-55 minutes | Higher draw, and heat forces you to break it up |
| Mostly stills, occasional clips | About 200-250 shots | Convert by time when mixing with video |
The 4K range is wide because it is not only a battery question. The body is small with limited room to shed heat, so a long 4K take trips a temperature warning first and you have to stop and let it cool. Those pauses stretch the pack’s usable time while shrinking the useful footage. Shooting 4K, the limit you hit is usually body temperature rather than charge.
What a ten-minute vlog actually costs
Many people budget by finished length and forget the shooting ratio. A ten-minute finished vlog usually involves 30-50 minutes of recorded material, because of retakes, angle changes and cutaways.
- Talking head: ten minutes finished, about 20 minutes of material, plus review and setup — roughly 30% of a charge. One pack covers two or three of these.
- Walking and talking: a shooting ratio closer to 1:4, so ten finished minutes needs about 40 minutes of material and consumes around 60% of a charge. One pack, one segment.
- Multiple locations: frequent power cycling, setting changes and review cost more than straight recording. Budget on 30 minutes of usable material per pack.
By that arithmetic, two vlogs in a morning needs two packs as an absolute minimum; three or more, or stills mixed in, needs three. Charge everything together at the hotel in the evening and start again the next day.
How many to carry, by situation
- Indoor talking head, half day: 2 packs. Swap when one runs out, with a power-bank top-up in between.
- City walk, full day: 3 packs. Stop-and-start shooting drains quickly, and the third is insurance.
- Travel over several days: 4 packs plus a two-bay charger. Two hours in the evening fills two packs, so the next day starts clean.
- Event coverage where you cannot stop: 4 packs and up, and consider external power. The 20 seconds it takes to change a pack may be exactly the moment you miss.
The NB-13L is light — under 30g each, so four come to just over a hundred grams. Since weight is not a burden, carry more than you think you need. This is helped by the NB-13L’s shared fit: the same pack works across the G7X, G9X and SX740, so extras are never wasted.
What actually saves power
- Default to 1080p. For most platforms 1080p at 25p or 30p is plenty, and it buys 30-50% more runtime than 4K while keeping the body cooler.
- Switch off Wi-Fi and Bluetooth. Leave them off when you are not transferring. The wireless module keeps scanning on standby — not a large draw, but a constant one.
- Drop the screen one step. Raise it outdoors if you must, but there is no need to run it flat out indoors. The screen is one of the biggest loads on this camera.
- Review less. Checking after every take is the most expensive habit in vlogging. Trust the monitor and check everything at the end.
- Switch off rather than waiting for sleep. The G7X III wakes quickly, so switching off costs you nothing and saves a meaningful amount of standby drain.
- Turn off unnecessary digital zoom and enhanced stabilisation. Electronic stabilisation crops and processes the image continuously, drawing more than optical stabilisation.
Stacked together, these usually buy about 20% more time per pack. Compared with buying a pack labelled 1800mAh, changing settings is the more certain gain.
Top-ups: where a power bank beats a spare
The G7X Mark III uses USB-C and supports in-body charging. With a power bank rated 5V/2A or more you can top up in a café or a car without hunting for an outlet. The catch is speed: a full charge from empty takes close to two hours, so it suits topping up while you shoot, not rescuing a flat pack before a take.
If you need long recordings from a fixed position — interviews, streams, lessons — swapping packs interrupts the image. That is where external power makes sense, along the lines of this dummy battery setup: an adapter replaces the pack and runs from mains or a large supply. Build quality varies widely on G7X dummy adapters, though, so confirm the output is 3.6V and regulated; the wrong voltage will damage the body outright.
If you travel for work, read the airline rules for lithium-ion packs in advance. The guide to lithium battery carry-on rules covers the detail, and although small packs like the NB-13L face fewer restrictions, there is still a quantity limit.
FAQ
Can one pack cover a whole event?
Usually not. At 1080p one pack gives 60-80 minutes of usable recording, and events tend to run past two hours. Rotate two packs, or use external power at a fixed position. Changing a pack interrupts recording, so plan ahead for anything important.
Why does 4K stop after a while?
Usually heat protection rather than a flat battery. The body is small and cooling is limited, so continuous 4K triggers a temperature warning. Pause for a few minutes, or switch to 1080p. Only if it stops very early with a cool body should you suspect the pack or card speed.
Can I record while charging?
Yes, depending on firmware and how power is supplied. With a USB-C power bank the camera may run on external power rather than charging, and the pack still drains slowly. Long charging-while-recording sessions heat both body and pack, especially in summer, so work in a ventilated spot.
Do spare packs have to be genuine?
No. Genuine packs are consistent and decode fully; a properly built compatible pack costs about half as much for similar capacity. The key is avoiding overrated products and packs with no protection board — the tell-tales are set out in the NB-13L buying guide.