topic Re: Rebel T6 E05, Auto focus not working sometimes in EOS DSLR & Mirrorless Cameras

Rebel T6 E05, Auto focus not working sometimes

hteng1995 — Mon, 27 Jan 2020 02:13:46 GMT

Hello. I have a Rebel T6 E05 with the basic 18-55 mm lens, and I recently have encountered an issue where I am sometimes unable to take a photo because the camera can't achieve a focus lock. I've tried toggling between MF and AF on the lens, and also the various AF modes (One shot, AI, Servo), and have also taken off the lens, turned it to MF setting, and manually extended and retracted the focusing lens, hoping to reset the motor inside. I've gotten it to the point where, during a bright sunny day, I can achieve a focus lock when the camera is fully zoomed in, and out.

However, it can only focus lock in-between when I am zooming back in after fully zooming out (and not the other way around). In other words, if I were to simply arbitrarly zoom a certain amount without fully zooming in and then zooming back out, I can't get a focus lock. Any ideas on why this may be the case?

Many thanks, in advance.

Re: Rebel T6 E05, Auto focus not working sometimes

ebiggs1 — Mon, 27 Jan 2020 15:28:05 GMT

It is a EOS T6 first of all.

However, do reset the camera to factory very first off. Menus, tools, clear all settings and all custom settings. If you don't know how to do this check your manual.

Then.....................

Take the lens off of your camera.

Put the lens in MF mode.

Twist the FOCUS ring (the tip of the lens) all the way to one side (extend it). You may hear a click noise or two, this is good, but don't FORCE the lens.

Twist the FOCUS ring all the way to the opposite side (retract it). Again, you may hear a couple of clicking noises. What we hope is happening is the focusing motor being put back into its proper place.

Put the lens back on the camera.

Put the lens in AF mode.

Turn the camera on.

Put the camera in AUTO or P mode.

Take a test photo.

Re: Rebel T6 E05, Auto focus not working sometimes

RobertTheFat — Mon, 27 Jan 2020 19:56:59 GMT

@ebiggs1 wrote:
It is a EOS T6 first of all.
However, do reset the camera to factory very first off. Menus, tools, clear all settings and all custom settings. If you don't know how to do this check your manual.

Then.....................
Take the lens off of your camera.
Put the lens in MF mode.
Twist the FOCUS ring (the tip of the lens) all the way to one side (extend it). You may hear a click noise or two, this is good, but don't FORCE the lens.
Twist the FOCUS ring all the way to the opposite side (retract it). Again, you may hear a couple of clicking noises. What we hope is happening is the focusing motor being put back into its proper place.
Put the lens back on the camera.
Put the lens in AF mode.
Turn the camera on.
Put the camera in AUTO or P mode.
Take a test photo.

What Ernie is suggesting is a well-known procedure to re-align the autofocus mechanism on an 18-55mm lens. Sometimes it helps and sometimes it doesn't, but it has even been recommended by Canon support.

But what Ernie didn't mention is that the usual reason the AF mechanism gets mis-aligned is that someone tried to focus manually while the lens was in AF mode. While there are many Canon lenses on which manual focus in AF mode is harmless, the basic 18-55 is not one of them. So if you do succeed in getting your lens working properly again, be sure, in the future, to turn off AF before focusing manually. Otherwise, you could cause the problem to recur.

Re: Rebel T6 E05, Auto focus not working sometimes

Waddizzle — Mon, 27 Jan 2020 23:39:16 GMT

@RobertTheFat wrote:
@ebiggs1 wrote:
It is a EOS T6 first of all.
However, do reset the camera to factory very first off. Menus, tools, clear all settings and all custom settings. If you don't know how to do this check your manual.

Then.....................
Take the lens off of your camera.
Put the lens in MF mode.
Twist the FOCUS ring (the tip of the lens) all the way to one side (extend it). You may hear a click noise or two, this is good, but don't FORCE the lens.
Twist the FOCUS ring all the way to the opposite side (retract it). Again, you may hear a couple of clicking noises. What we hope is happening is the focusing motor being put back into its proper place.
Put the lens back on the camera.
Put the lens in AF mode.
Turn the camera on.
Put the camera in AUTO or P mode.
Take a test photo.
What Ernie is suggesting is a well-known procedure to re-align the autofocus mechanism on an 18-55mm lens. Sometimes it helps and sometimes it doesn't, but it has even been recommended by Canon support.

But what Ernie didn't mention is that the usual reason the AF mechanism gets mis-aligned is that someone tried to focus manually while the lens was in AF mode. While there are many Canon lenses on which manual focus in AF mode is harmless, the basic 18-55 is not one of them. So if you do succeed in getting your lens working properly again, be sure, in the future, to turn off AF before focusing manually. Otherwise, you could cause the problem to recur.

I do not believe many people are trying to focus manually when this occurs. Manual focusing is not something the average novice DSLR owner would do. I think it is more likely that they wanted to turn the zoom ring, but turned the focus ring, instead.

Re: Rebel T6 E05, Auto focus not working sometimes

wchettel — Tue, 28 Jan 2020 06:41:51 GMT

@ebiggs1 wrote:
...
Then.....................
Take the lens off of your camera.
Put the lens in MF mode.
Twist the FOCUS ring (the tip of the lens) all the way to one side (extend it). You may hear a click noise or two, this is good, but don't FORCE the lens.
Twist the FOCUS ring all the way to the opposite side (retract it). Again, you may hear a couple of clicking noises. What we hope is happening is the focusing motor being put back into its proper place.
Put the lens back on the camera.
Put the lens in AF mode.
Turn the camera on.
Put the camera in AUTO or P mode.
Take a test photo.

Does this procedure work on Canon STM lenses? I was curious, so I tried this on my Canon EFS 18-55mm f4-5.6 IS STM lens. There is NO stop when I turn the focus ring in either direction. And, the lens does not extend or retract when I turn this ring. Can you clarify??

Re: Rebel T6 E05, Auto focus not working sometimes

Ray-uk — Tue, 28 Jan 2020 10:31:13 GMT

No this procedure does not work with the STM lenses, the focus ring on these has no mechanical connection to the focus motor.

The focus ring on an STM lens has only an electrical connection and the shutter button needs to to be held down halfway to activate the focus motor circuitry before the focus ring can be used, because of the nature of the electrical connection there is no stop at either end of the focus ring.

Re: Rebel T6 E05, Auto focus not working sometimes

RobertTheFat — Tue, 28 Jan 2020 15:05:31 GMT

@Waddizzle wrote:
@RobertTheFat wrote:
@ebiggs1 wrote:
It is a EOS T6 first of all.
However, do reset the camera to factory very first off. Menus, tools, clear all settings and all custom settings. If you don't know how to do this check your manual.

Then.....................
Take the lens off of your camera.
Put the lens in MF mode.
Twist the FOCUS ring (the tip of the lens) all the way to one side (extend it). You may hear a click noise or two, this is good, but don't FORCE the lens.
Twist the FOCUS ring all the way to the opposite side (retract it). Again, you may hear a couple of clicking noises. What we hope is happening is the focusing motor being put back into its proper place.
Put the lens back on the camera.
Put the lens in AF mode.
Turn the camera on.
Put the camera in AUTO or P mode.
Take a test photo.
What Ernie is suggesting is a well-known procedure to re-align the autofocus mechanism on an 18-55mm lens. Sometimes it helps and sometimes it doesn't, but it has even been recommended by Canon support.

But what Ernie didn't mention is that the usual reason the AF mechanism gets mis-aligned is that someone tried to focus manually while the lens was in AF mode. While there are many Canon lenses on which manual focus in AF mode is harmless, the basic 18-55 is not one of them. So if you do succeed in getting your lens working properly again, be sure, in the future, to turn off AF before focusing manually. Otherwise, you could cause the problem to recur.
I do not believe many people are trying to focus manually when this occurs. Manual focusing is not something the average novice DSLR owner would do. I think it is more likely that they wanted to turn the zoom ring, but turned the focus ring, instead.

Fair enough, it could be inadvertent. But the effect is the same. One has to be careful not to turn the focus ring while the lens is in AF mode.

Re: Rebel T6 E05, Auto focus not working sometimes

RobertTheFat — Tue, 28 Jan 2020 15:14:31 GMT

@Ray-uk wrote:
No this procedure does not work with the STM lenses, the focus ring on these has no mechanical connection to the focus motor.

The focus ring on an STM lens has only an electrical connection and the shutter button needs to to be held down halfway to activate the focus motor circuitry before the focus ring can be used, because of the nature of the electrical connection there is no stop at either end of the focus ring.

Ray is of course correct: the procedure does not work on an STM lens. But neither does it have to. Because the focusing mechanism is entirely electrical, no mechanical parts will get grunched if you try to focus manually while the lens is in autofocus mode.

Re: Rebel T6 E05, Auto focus not working sometimes

Stephen — Tue, 28 Jan 2020 15:21:57 GMT

One of my favorite benefits of the STM system is not having to worry about switching to MF when storing basic lenses. When I upgraded to the Rebel T7i from my trusty Rebel T2i, I also upgraded all of my lenses (nifty 50, 18-55, 55-250). If the lens has an STM option available, I always recommend it, because of inadvertantly grabbing the focus ring instead of zoom, or leaving it in AF when storing it and jamming the gears.

BTW, you guys are all amazing, and we truly appreciate your help!

Re: Rebel T6 E05, Auto focus not working sometimes

ebiggs1 — Wed, 29 Jan 2020 06:35:11 GMT

" I always recommend it, because ... leaving it in AF when storing it and (possibly) jamming the gears."

The Canon EF 85mm f/1.2L II USM Lens is the same way and it is not a STM.

Re: Rebel T6 E05, Auto focus not working sometimes

Stephen — Thu, 30 Jan 2020 19:29:13 GMT

Oh, Ernie. I only get to play with L-series lenses for work! I don't make Red Ring money, though!