Batteries and AF

[bseitz234]

Question for all of the collective wisdom here:

The other day, I let my sister borrow my 7d. She's used to my dad's 60D, and probably getting a rebel of her own, so I wasn't too concerned about her messing anything up. When she gave it back to me, it wasn't AFing- with any lens, regular or live view, nothing. When I MFd in one-shot mode, I got a focus recognition beep. Checked all the connectors, they were all clean. Finally, I looked at a pin diagram, and seeing that a pin provides 6v for the lens AF motor (something I logically knew, that was just the inspiration) I popped in a fresh battery. Suddenly, AF worked again!

My questions:
Has anyone ever observed behavior, where a battery shows 2 bars of remaining charge on the top LCD, and the camera takes shots, but doesn't have power to AF?
The battery I had in was OEM. I swapped in a Wasabi power LP-E6 clone- any OEM/3rd party compatibility issues? I'm inclined to think no, since the OEM was the one that caused the problem.
Should I do anything? At this point, this is purely an exercise in intellectual curiosity- that wasabi power LP-E6 has now taken 1,000 shots without issue, so I'm curious more than concerned.

Thanks!
Brian

 

[East Wind Photography]

I've never seen that. Been using t2i, 60D, 7D and 5DIII. All use the LP-E6 (thanks Canon for at least being consistent for a few years). It could just be a defective battery. How old is it? They do wear down after each use/charge cycle (other electronics too inside that can fail).

If you put the OEM battery back in does the problem return?

Question for all of the collective wisdom here:

The other day, I let my sister borrow my 7d. She's used to my dad's 60D, and probably getting a rebel of her own, so I wasn't too concerned about her messing anything up. When she gave it back to me, it wasn't AFing- with any lens, regular or live view, nothing. When I MFd in one-shot mode, I got a focus recognition beep. Checked all the connectors, they were all clean. Finally, I looked at a pin diagram, and seeing that a pin provides 6v for the lens AF motor (something I logically knew, that was just the inspiration) I popped in a fresh battery. Suddenly, AF worked again!

My questions:
Has anyone ever observed behavior, where a battery shows 2 bars of remaining charge on the top LCD, and the camera takes shots, but doesn't have power to AF?
The battery I had in was OEM. I swapped in a Wasabi power LP-E6 clone- any OEM/3rd party compatibility issues? I'm inclined to think no, since the OEM was the one that caused the problem.
Should I do anything? At this point, this is purely an exercise in intellectual curiosity- that wasabi power LP-E6 has now taken 1,000 shots without issue, so I'm curious more than concerned.

Thanks!
Brian

 

[rpt]

Question for all of the collective wisdom here:

The other day, I let my sister borrow my 7d. She's used to my dad's 60D, and probably getting a rebel of her own, so I wasn't too concerned about her messing anything up. When she gave it back to me, it wasn't AFing- with any lens, regular or live view, nothing. When I MFd in one-shot mode, I got a focus recognition beep. Checked all the connectors, they were all clean. Finally, I looked at a pin diagram, and seeing that a pin provides 6v for the lens AF motor (something I logically knew, that was just the inspiration) I popped in a fresh battery. Suddenly, AF worked again!

My questions:
Has anyone ever observed behavior, where a battery shows 2 bars of remaining charge on the top LCD, and the camera takes shots, but doesn't have power to AF?
The battery I had in was OEM. I swapped in a Wasabi power LP-E6 clone- any OEM/3rd party compatibility issues? I'm inclined to think no, since the OEM was the one that caused the problem.
Should I do anything? At this point, this is purely an exercise in intellectual curiosity- that wasabi power LP-E6 has now taken 1,000 shots without issue, so I'm curious more than concerned.

Thanks!
Brian

Q1: Nope. Never.
Q2: I have 3 OEMs and one non-OEM. I have let go of the non-OEM because it did not hold charge. AF was not an issue with it. Even the last shot before the camera died would AF.
Q3: So a bit of basic electrical engineering. If that particular battery is not able to deliver 6V to AF when it shows 2 bars, it could be that the battery is faulty. It may be that the internal resistance of the battery is high. It would still generate a voltage that would be considered ok (2 bars), but when it has to deliver the current to the USM to AF, the internal resistance would drop the voltage and hence unable to AF. Then again, this is my best guess (intellectually best guess). Well, I know your question was should you do anything? The answer to that one is a resounding yes!
If it is under any sort of warranty, take it back. Internal resistance of a battery is not a function of its charge. It is easily measured. Canon should be able to tell you if your battery is good or not. If it is not, you can leave it with them to recycle it.

Here are some questions I have:
So did you ask your sis if she found that the camera did not AF before she returned it?
Are the battery terminals dirty?
How many pictures can you shoot till this battery goes to 2 bars? And how many can you shoot till the others go to 2 bars? I don't want you to up your shutter count just to answer this question . Oh! I am assuming the other batteries keep AFing even when they get to 1 bar. If not, we need to have a whole different discussion...

Hope this helps.

 

[Mt Spokane Photography]

I've never seen the issue, on either of my 7D's or with several OEM batteries. Something is wrong if autofocus stops working. It could be a lens issue, or a body, or a bad battery. If a battery develops a high internal resistance, its power output will drop, but the camera should show it.
The battery has electronics in it that tells the camera its state of charge, so it would be my first suspect.

 

[bvukich]

This is (highly) unlikely, but I'll throw it out there any way...

Do you use magic lantern?

On my 60D I had back button AF magically turn itself on, and then back off shortly thereafter. In my perception AF just stopped working, then started again. The second time it happened is when I figured out what was happening. But then it hasn't happened since.

I suspect it was caused by ML, but I have no actual proof. ML saving it's settings on the card is the main reason I suspected it. It may be completely unrelated to ML though.

 

[RC]

I'll throw this one out there

I had 3 OEM LP-E6 batteries for my 7D (1 original, 2 spares). When I got my 5D3, one of the spares would not power on my 5D even though it worked just fine on my 7D. Anyway, long story short, I was the victim of a counterfeit LP-E6 and was truly fooled by the almost perfect replication of the fake--even the packaging was near perfect. Not suggesting yours is counterfeit but it might be worth checking into.

Otherwise, sounds like something internal happened (drop, bang) damaging the battery causing the output voltage to be too low.

 

[Mt Spokane Photography]

This is (highly) unlikely, but I'll throw it out there any way...

Do you use magic lantern?

On my 60D I had back button AF magically turn itself on, and then back off shortly thereafter. In my perception AF just stopped working, then started again. The second time it happened is when I figured out what was happening. But then it hasn't happened since.

I suspect it was caused by ML, but I have no actual proof. ML saving it's settings on the card is the main reason I suspected it. It may be completely unrelated to ML though.

It is also a known issue with the 5D MK III and FoCal Pro. Sometimes the software does not reset the shutter button to half press = focus after remapping it. It happened to me, and it took me a few minutes to discover the issue. At the time, I suspected FoCal, but tonight, I found it in the manual when I read it through (all 132 pages). I learned a lot, and was amazed at how much it has grown since I bought it in early January 2012.

 

[bseitz234]

Thanks all for the replies!

Lets see if I can answer all these questions:
-I do not use ML; not that crazy a question, I've considered it, but no, I'm using factory firmware.
-Longer version of the anecdote: she said she was manual focusing because the camera wasn't focusing, but she thought it was fine at the beginning. Looking at her shots, she nailed some running dogs, so I'm pretty sure it was fine when she got it, and died during that day.
-I have not really tested any of the batteries, since I usually recharge at the end of a day of shooting. But I have fired off 2k frames in one day of ski racing, and not had to change battery. Unfortunately don't remember which battery that was... Statistically speaking, twice as likely to be a third-party one, right?
-battery terminals look clean to me
-both third party batteries AF right down to one bar.
-this OEM battery is ~5months old, can't have more than half a dozen load-cycles. Came with my 7d when I got it, refurb. Makes me less likely to bother returning it... If it is a faulty battery it seems more worth my time to recycle it and get another $15 wasabi power one... They've been great in my gopro for 2 years, and so far so good in this context as well.

Edit: because I got it from canon direct, I'm inclined to think its genuine. Now, it may be refurbed and already have a ton of load cycles, but I think it was in retail packaging...

 

[RC]

From what everything I've read here on CR, I wouldn't be worry about any 3rd party batteries, just those damn counterfeits. Sounds like yours are all fine.

 

[rolsskk]

Thanks all for the replies!

Lets see if I can answer all these questions:
-I do not use ML; not that crazy a question, I've considered it, but no, I'm using factory firmware.
-Longer version of the anecdote: she said she was manual focusing because the camera wasn't focusing, but she thought it was fine at the beginning. Looking at her shots, she nailed some running dogs, so I'm pretty sure it was fine when she got it, and died during that day.
-I have not really tested any of the batteries, since I usually recharge at the end of a day of shooting. But I have fired off 2k frames in one day of ski racing, and not had to change battery. Unfortunately don't remember which battery that was... Statistically speaking, twice as likely to be a third-party one, right?
-battery terminals look clean to me
-both third party batteries AF right down to one bar.
-this OEM battery is ~5months old, can't have more than half a dozen load-cycles. Came with my 7d when I got it, refurb. Makes me less likely to bother returning it... If it is a faulty battery it seems more worth my time to recycle it and get another $15 wasabi power one... They've been great in my gopro for 2 years, and so far so good in this context as well.

Edit: because I got it from canon direct, I'm inclined to think its genuine. Now, it may be refurbed and already have a ton of load cycles, but I think it was in retail packaging...

I'd go ahead and clean not only the battery terminals, but the lens terminals as well. Easiest thing to do to eliminate a possible cause, and if that doesn't work, proceed to troubleshoot.

 

[East Wind Photography]

Interesting that it was a refurb. Possible it was returned...camera was checked out but not the battery. Put up for sale as a refurb. I've often found...no every time I've found...that buying a refurb also buys you the previous owners issue. I generally stay away from refurbs. That being said, every refurb issue I found was always fixed under warranty...but it's the hassle you deal with to save a few dollars.

Thanks all for the replies!

Lets see if I can answer all these questions:
-I do not use ML; not that crazy a question, I've considered it, but no, I'm using factory firmware.
-Longer version of the anecdote: she said she was manual focusing because the camera wasn't focusing, but she thought it was fine at the beginning. Looking at her shots, she nailed some running dogs, so I'm pretty sure it was fine when she got it, and died during that day.
-I have not really tested any of the batteries, since I usually recharge at the end of a day of shooting. But I have fired off 2k frames in one day of ski racing, and not had to change battery. Unfortunately don't remember which battery that was... Statistically speaking, twice as likely to be a third-party one, right?
-battery terminals look clean to me
-both third party batteries AF right down to one bar.
-this OEM battery is ~5months old, can't have more than half a dozen load-cycles. Came with my 7d when I got it, refurb. Makes me less likely to bother returning it... If it is a faulty battery it seems more worth my time to recycle it and get another $15 wasabi power one... They've been great in my gopro for 2 years, and so far so good in this context as well.

Edit: because I got it from canon direct, I'm inclined to think its genuine. Now, it may be refurbed and already have a ton of load cycles, but I think it was in retail packaging...