E-M5 EVF battery drain

For those who have been guessing about the power consumption of the E-M5, here are some details that might interest you:-

1. EVF consumes only about 10mA less than the rear LCD.

2. When the LCD/EVF is dark (such as at night or with lens cap on), current consumption is about 100mA less.
3. Video mode consumes about 100mA more than in still mode.
4. Normal current draw is between 350mA to 450mA in still mode.
5. Shutter action results in a burst current draw of over 1.2A.
6. Eye-Fi Pro X2 8GB in active-search mode adds approximately 50mA draw.
7. Grip alone, unattached to the body, shows no measurable current draw.
8. When camera is left to go to sleep, it still draws 100mA (screen is off).

9. After the preset time, the camera powers-down and in this mode, there is no appreciable current draw.

10. When powered through the grip, the system draws about 40-50mA more than when powered without the grip.

11. In power-down/OFF mode, there is no measurable current draw with the grip attached or unattached.

So far, based on these readings, one would expect the camera to be able to operate continuously for about 2.5 to 3 hours, depending on what is being displayed on the screen, type of Wi-Fi card used, and so on. Turning off the camera in between shots will obviously represent tremendous power savings since the sleep mode is very power hungry. If you use video modes, expect battery life to be shortened even more (about 2-hours continuous operation).

Note: These readings were all made at the terminal voltage of 8.4V. Actual current draw will increase as terminal voltage drops due to the switching power supplies in these modern devices. As it does, efficiencies will also change a bit. The EVF/LCD were left at default brightness. If you have reduced the brightness, you may have some power savings there and extend battery life a bit (at the expense of usability I suppose.)

When using the DSTE third-party battery - the battery indicator will show full-scale until the terminal voltage reaches 7.1V. At this point, you get the orange indicator with one segment of the battery left. Upon powering up - anything above 7.4V will be displayed with a battery-full indication. At no point in the testing did the indicator show a 2-segment battery. This may be due to the lack of special communications between the battery and the camera.

Daniel Wee