Camera battery life: if you measure it, you measure it wrong
19.6.2020
Translation: machine translated
There is a standardised method for measuring the battery life of a camera. Unfortunately, the method also has its weaknesses. There is no comparability across all brands and camera types.
Videos need more power than photos. Shooting with flash requires more power than without. If you take a lot of photos very quickly, you can take more photos on one battery charge than if you always take a few minutes in between. And so on. Depending on how you use the camera, the battery will sometimes last longer, sometimes less.
It is therefore not very meaningful when a user or a tech journalist writes that they took this and that and the battery lasted for 500 photos. A standardised test procedure is needed to compare the battery life of different cameras. And this procedure exists: the CIPA standard.
However, this standard unfortunately also has its flaws.
The battery test according to the CIPA method
The CIPA (Camera & Imaging Products Association) is the Japanese association of manufacturers of cameras and other photographic hardware (lenses, filters, etc.). In 2003, it defined a test procedure to measure battery life.
Some important points of the procedure:
- In principle, the test should be carried out with the default settings.
- Every second shot must be taken with flash.
- After each shot, the zoom motor of the lens must be moved to its full length, i.e. from maximum wide angle to maximum telephoto or vice versa
- The main screen should always be switched on if possible and used as a viewfinder
The test consists of the following procedure:
- Switch on
- 30 seconds for zoom, flash on/off and other settings if necessary
- Take photo
- again 30 seconds for operations
- take the next photo
- the camera is switched off and on again every 10th photo
The whole process is repeated until the camera switches off due to low battery. It is permitted to switch it on again afterwards and continue to operate it until it finally switches off, if this is possible.
The problems of the standard
There are a few obvious problems with this method. Cameras that do not have a flash have an advantage: in this case, all shots are simply taken without a flash. Cameras without a zoom have a similar advantage.
In addition, it is not defined how strong the flash must be set. In automatic mode, the flash consumes quite a lot or almost no power, depending on the situation.
In 2003, when the method was defined, there were no mirrorless system cameras and only a few digital SLR cameras. The CIPA process is clearly aimed at compact cameras.
Today, a different method would certainly make more sense. However, any change to the method would mean that cameras from earlier years could no longer be compared with current models.
The biggest problem, however, is that the cameras are tested by the manufacturers themselves. And obviously not all manufacturers test in the same way. This is most noticeable with SLR cameras. Canon has much worse values for comparable SLR cameras than Nikon. Example: According to the manufacturer, the Canon EOS 5D IV can take 900 photos with the LP-E6N battery (1865 mAh), while Nikon takes an incredible 1840 photos with a similarly sized battery (1900 mAh).
The fact that Nikon's processors, sensors or screens would be much more efficient is out of the question, as Canon and Nikon have very similar values for mirrorless cameras. Canon is even slightly better. Example: The Canon EOS R achieves 370 shots (battery 1865 mAh), the Nikon Z 6 330 shots (1900 mAh).
Strange specifications for SLR cameras
The viewfinder of an SLR camera works without power. If you mainly take photos via the viewfinder, a battery will last much longer than with a mirrorless camera. However, the CIPA regulations stipulate that the monitor must be used as a viewfinder. With SLR cameras, this is called Live View.
«During the test, the colour screen must be continuously switched on in the mode in which it can be used as a viewfinder. If the screen switches off automatically during the test or switches to a mode, it should be immediately reset to viewfinder mode.»
With SLR cameras, however, it can be argued that pre-2009 models cannot use the monitor as a viewfinder at all and that newer cameras that can (but do not have to) are at a disadvantage. The comparability would be gone.
Therefore, my first assumption was that Nikon would carry out the test without Live View and Canon with it.
Nikon actually states that Live View is not used. Nikon states this, for example, in a footnote in the user manual of the D850. Surprisingly, however, Canon also makes the marginal note in the specifications of the 5D Brand IV: "Shooting via the viewfinder."
So both groups do not use Live View for metering. This at least clarifies why SLR cameras generally have much better values than mirrorless system cameras. However, the major differences between Canon and Nikon remain a mystery.
Measure it yourself?
Whether it's battery tests, CPU benchmarks or whatever: I find it fundamentally problematic when manufacturers carry out performance tests themselves. This would require an independent test centre.
Theoretically, I could test a Canon and a Nikon camera myself using the CIPA method and compare them with the manufacturer's specifications. Unfortunately, I don't see any way to automate the test correctly. With Nikon, automatic interval shooting does not allow SLR Live View. I don't know about Canon. In addition, the camera would have to be switched off after every tenth picture. And in my case, since the camera has a flash, it would also have to be switched on and off constantly. If the battery lasts for 1200 pictures, I would be busy taking stupid test shots for 10 hours per camera. I'm not doing that to myself.
However, I'm planning some other tests to find out how much power the various camera operations require. Stay tuned! You can follow me as an author (button in the author profile), then you will be notified by e-mail about new articles. <p
David Lee
Senior Editor
David.Lee@digitecgalaxus.chMy interest in IT and writing landed me in tech journalism early on (2000). I want to know how we can use technology without being used. Outside of the office, I’m a keen musician who makes up for lacking talent with excessive enthusiasm.