# Low Battery causing exposure changes



## offtheroad (May 10, 2016)

I have a Canon 5D MK II and noticed my exposure went from 1/60 to 1/8 and just to be curious why, I noticed my battery was down to about 20%. I put a fresh battery in and exposure went back up to 1/60. I called canon and may need to send it in. But it will cost me. Any idea why the battery could cause that. Canon tech people had no idea. Thanks


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## clel miller (May 11, 2016)

I am a film guy, with old cameras, but.......
The battery was almost dead, and neither You or Canon can figure out why that might effect the meter.....is that what you are saying.?


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## spiralout462 (May 11, 2016)

I'm willing to bet that something else changed in addition to the shutter speed.  Perhaps aperture size, ISO, or light.  I highly doubt the battery power is the reason your shutter speed dropped.


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## Derrel (May 12, 2016)

spiralout462 said:
			
		

> I'm willing to bet that something else changed in addition to the shutter speed.  Perhaps aperture size, ISO, or light.  I highly doubt the battery power is the reason your shutter speed dropped.



Yeah...sounds very odd that battery reserve level would affect light metering; was there any stray, ambient light that might have entered through the rear eyepiece, thus affecting the metering? At times, bright light, or just "light" entering the rear eyepiece can inflate the light meter readings. Or something can happen when the camera is turned off, such as exposure compensation that was enabled is erase on the battery swap and the re-start, etc.. Let's hope there's nothing wrong with the camera, and that this is just an anomaly.


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## clel miller (May 12, 2016)

Put the old battery back in.


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## astroNikon (May 12, 2016)

I 2nd.  Put the old battery back in and swap back and forth until you figure it out.

Hope you aren't using flash either .. I wonder if the flash intensity would change with a drained battery.


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