EOS 7e/USM IS lens battery drainage???

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Hi Everyone!

I have a new 7e body and 28-135 IS lens. Is all power to the lens shut off when the camera is shut off? I keep forgetting to turn the lens' IS switch on when I turn on the camera. I would like to just leave the IS on all the time but am afraid of battery drainage. Does anyone know if the battery would drain with the camera off and the IS on? Thanks, Bill

-- Bill (williamlcook@earthlink.net), November 16, 2000

Answers

If the new Elan 7 is similar to many other EOS cameras,as long as you turn the camera to the "L" or "locked" (off) position, the lens should not be sucking any electrons from the battery, regardless of whether the IS switch is left on. However, even when the camera is turned off, there is a tiny amount of ongoing power consumption to power (for example) the few LCD symbols that remain present even when the camera is off. Remove the battery, and you should find that these few remaining LCD symbols disappear. Check me on this to see if I'm correct.

-- kurt heintzelman (heintzelman.1@osu.edu), November 16, 2000.

Kurt's right about no power going to the lens when the camera is off, but then there's no power being used by the lens when the camera is left on either. The only time the IS drains power is when the IS is active (when the shutter button is down). The AF & aperture motors are the same way, they only draw power when they are actually in motion.

So the bottom line is; even if you leave your camera on there is very low battery drain. I have left my Elan IIe with 28-135 IS on in the bag or weeks at a time without much life drained from the battery. Evidently light metering and all the other circuits don't drain much while the camera is on idle either.

-- Jim Strutz (j.strutz@gci.net), November 16, 2000.


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