Back in 2012, I remember that single event where we decided to run on batteries... a full 360 with 28 cameras running on batteries. Talk about a nightmare. I still hate myself for having allowed that. Things would be simpler today as we're not using the buggy software we were using back then, but please, get serious with your power for your cameras! You don't want to change your batteries during a live event.
The only case where we're using batteries is for portable rigs where it's more efficient to use branded Canon batteries (they last for very long)
Before getting started with the equipment, let's get through proper names for the equipment
- Coupler: this is a plastic piece (with some electronics inside) that goes inside the camera instead of the battery (it has the same shape).
- Power supply: This is a brick that converts regular alternative current into a continuous current source suitable for electronic devices like a camera
- Power cable: it is what it is!
No doubt that Esper is the best option as of today. They totally took this market at a moment where it was extremely hard to get genuine Canon power adapters. We highly recommend going with them.
- Esper powerbox: "Safe & reliable way to power multiple cameras simultaneously." (I confirm!) https://www.esperhq.com/product/multi-camera-power-supply-powerbox/ . This can power up to 6 cameras. We have tons of those, they work perfectly.
- Genuine Canon power adapters: these can be found on Canon websites, but they are usually 100$USD/unit and can be hard to find. You'll need one per camera, making everything look messier.
- No-name cheap power adapters: we have a few that are ok, but most are likely to give you power issues. Here's an example: https://www.amazon.com/Power-Adapter-Canon-550d-Ack-e8/dp/B00BLZX5I2 . This might work ok for a single camera in non critical situations, but for your bullet-time rig, this can be quite stressful when you're losing your cameras after you take a shot due to the low quality of these couplers / power adapters
- A cheap but somehow reliable option: Echpow is making these nice little usb adapters which work well when paired with proper power. We use those with Anker 60W 10-Port USB Wall Charger
- you'll have to make sure that you order the right item for your camera. The couplers are just like batteries. They are going to work only for the specified models.
- Couplers can be purchased separately via Esper or Tethertools (but not with Canon)
For reference, here's a side cut of 3 different couplers (SL1 / 100d)