My 2nd T6s has the same flaw.

[PajamaGuy]

While shooting one of my grandson's  AAU baseball game, my 3-week old T6s exhibited a flaw.  Although I can't recall the exact steps, and therefore can not duplicate the flaw on-demand, I've experienced it with my T3i, and both T6s'.

When using Back-Button-Focus in conjunction with AI Servo and Continuous Shutter and while taking rapid groups of sequential shots, the BBF button (AE/FE Lock) magically becomes a shutter-release button.  And when that happens, the actual shutter button sometimes triggers the Continuous Shutter action which then keeps shooting even when all buttons are released.  (flipping power off/on resets it).

When I explained the issue to Canon, they had me send in my 1st T6s, and they sent me a new one.  The same day I received the replacement it too exhibited the flaw. - BUT - I do love the camera and would buy it again!

PJ

[Tim]

Hello PajamaGuy,

This is certainly an interesting issue that you've presented to us.  I am curious if you may have activated the auto exposure bracketing by accident.  As if that is set and you're in continuous shooting- it will capture images even if you remove your finger from the shutter button until it's captured however many images are set in that sequence. 

If you would'nt mind reply to this post and let the community know what lens you are using on the camera at the time.  Also, does the same effect happen when you are not using the back button focusing?

[PajamaGuy]

Thanks - I'm pretty sure AEB was not active - and we're talking 5-8 images before I can push enough buttons to kill it.  Power off works too.

For the T3i and the first T6s, it was my 55-250 IS II.  For the second T6s, it was my 55-250 STM.

I have shot 3 6-inning baseball games since, and it hasn't screwed up. 

An interesting note - My new 55-250 STM was annoying as it went to "sleep" frequently while I was substituting my T3i - but, it has only gone to sleep once with the T6s, AND when it did, it didn't rack forward & back when it awoke!  Much better!

I use BBF whenever i'm continuous shuttering.

I can check anything you'd like - and will post here if/when it repeats.

Dave

[amfoto1]

Interesting.... I shoot a lot of sports and have probably taken several million photos using BBF... And have never seen this happen. 

I've been shooting with Canon cameras and lenses for going on 15 years, film and digital. Have owned and used about dozen different cameras extensively (7 or 8 different models)... and have occasionally used some other Canon models (though never T6i/T6s or T3i). Learned to do Back Button Focusing with my first Canons and have used it as my default setting ever since. About the only time I take the cameras out of BBF setup now is on the rare occasion when I lend a camera to someone and they don't know how to use BBF.

Not sayin' it didn't happen... some Canons I've used have had their "quirks" (BG-E2 battery grips would loosen while shooting and the camera would occasionally shut down unexpectedly... but the fix was simple and the "issue" was pretty widely known). Just seems odd that you've seen it occur on 3 different cameras (and two different models) in a relatively short time.

STM lenses are "fly by wire", meaning that their operation is electromechanical and they require power to operate. So I am guessing that the lens "goes to sleep" and "wakes back up" along with the camera (you can set the duration before sleep mode on most Canon cameras... though generally you'll want to make it relatively short to save battery charge.) STM also is relatively new technology (I think the 1st lenses with it appeared mid-2012), so later camera models are "optimized" to work better with them. T3i preceded the first STM lenses by a little more than a year. T6i/T6s are brand new models that are no doubt designed to take full advantage of STM lenses.

***********

Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7D(x2), 50D(x3), some other cameras, various lenses & accessories
FLICKR & EXPOSUREMANAGER 

[PajamaGuy]

...I hear ya!  I'm certainly not as experienced; I'm a little over 50,000 frames with all 3 combined.  I can't think of anything in common for all instances except for "Canon", "Rebel", and "BBF".  And it's more of a nuisance than a problem; it's only happened once (about 10,000 frames ago) with the current T6s, and I can recover pretty quickly.

Your setup/use of BBF pretty much duplicates mine. 

Thanks !

Dave

[PajamaGuy]

I'd just completed a 20-shot, 4-second sequence of 7-year-old flag footballers, and I'd dropped the camera to hang from my neck while I waited for the next down.  I'd shot 537 frames so far this morning, with many 10-15 shot sequences; a few over 20. Settings were, BBF, Continuous Shutter, AI Servo, Tv-1/1000, ISO-Auto, 55-250 IS STM.  As I closed my hand on the grip, I intentionally half-pressed the shutter with my index finger.  Yes, it was a half-press, and in face a very light half press.

The continuous shutter started- I immediately removed my finger from the Shutter Button (before the 2nd exposure) - and I let go of the camera - it kept shooting.  I grabbed the grip and fully depressed then released the shutter - it kept going.  I thumbed the BBF and released - it kept going.  I alternately pressed and released the Shutter and the BBF.  It kept going, then it finally quit.

17 frames had been exposed.  (this time I'm keeping them). 

I went on to shoot 98 more frames, many of them sequences.  Without incident.

Then I drove across town to another grandson's AllStars baseball game.  641 more frames, all settings the same.  Several continuous shutter sequences, but none over 10-12 frames.  No problems, no issues.

(Check out the image - that's gonna leave a mark!)

[amfoto1]

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@PajamaGuy wrote:

....

Check out the image - that's gonna leave a mark!

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Yeah, but it's also good for a free and easy stroll to first base.

It's still baffling... why you are gettng those long bursts when using BBF!

***********

Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7D(x2), 50D(x3), some other cameras, various lenses & accessories
FLICKR & EXPOSUREMANAGER 

[RobertTheFat]

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@amfoto1 wrote:

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@PajamaGuy wrote:

....

Check out the image - that's gonna leave a mark!

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Yeah, but it's also good for a free and easy stroll to first base.

If it actually hit him. It looks as though he's trying to back out of the way.

It's still baffling... why you are gettng those long bursts when using BBF!

The one good side of this problem is that it sounds like something that should be readily fixable in firmware, once the Canon technicians get their heads around what's happening.

[PajamaGuy]

"If it actually hit him. It looks as though he's trying to back out of the way."

The pitcher told me it did hit his elbow (immediately before this shot) - he actually got a pinch runner.

"The one good side of this problem is that it sounds like something that should be readily fixable in firmware, once the Canon technicians get their heads around what's happening."

I agree - I just wish I could identify the steps necessary to reproduce it "on demand".  I was an I/T Director for the Space Shuttle Program, and I know the frustration of, "It shouldn't happen, I believe it does, but I'd like to see it for myself!"

PJ

[RobertTheFat]

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@PajamaGuy wrote:

"If it actually hit him. It looks as though he's trying to back out of the way."

The pitcher told me it did hit his elbow (immediately before this shot) - he actually got a pinch runner.

"The one good side of this problem is that it sounds like something that should be readily fixable in firmware, once the Canon technicians get their heads around what's happening."

I agree - I just wish I could identify the steps necessary to reproduce it "on demand".  I was an I/T Director for the Space Shuttle Program, and I know the frustration of, "It shouldn't happen, I believe it does, but I'd like to see it for myself!"

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All of us who work in IT are familiar with that frustration. And we all know how easy it is for almost any embedded computer to fall victim to timing issues that can be very difficult to track down.