7d Focus Issues

MirandaH22
Contributor
I purchased a used 7d in February. It came with a Canon 50mm 1.8. It was working great up until last week after a photo session. It gets super humid where I live so I thought maybe that was the problem but my AF was hit and miss. I just took some photos Friday and not one of them were sharp, even at f/5. No spot on the image was sharp so it’s not missing focus, there’s totally no focus. I tried a lens calibration but everything was still soft. I have not done an internal cleaning on the camera so what’s the likelihood it’s dirt messing up my AF and not something more serious? How would I know what’s causing the AF issues?
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@MirandaH22 wrote:
I purchased a used 7d in February. It came with a Canon 50mm 1.8. It was working great up until last week after a photo session. It gets super humid where I live so I thought maybe that was the problem but my AF was hit and miss. I just took some photos Friday and not one of them were sharp, even at f/5. No spot on the image was sharp so it’s not missing focus, there’s totally no focus. I tried a lens calibration but everything was still soft. I have not done an internal cleaning on the camera so what’s the likelihood it’s dirt messing up my AF and not something more serious? How would I know what’s causing the AF issues?

The most common explanation for that behavior is accidentally switching the lens to MF. So be sure to rule that out.

Bob
Philadelphia, Pennsylvania USA

MirandaH22
Contributor
I did switch it from AF to MF a few times to make sure it wasn’t the problem. I don’t have any other lenses yet to see if the problem is because of the lens or the camera itself. I was going to order a new lens soon but now that I’m having problems I’m not sure if I need to order a new 50mm or go for the lens I want

Can you hear or see the lens move when you half press the shutter button, if not then you may have a faulty lens.

Have you accidently changed the menu settings to back button focus.

MirandaH22
Contributor
The lens does move. I tried focusing in live view but it doesn’t help. I use back button focus normally. The lens searches for several seconds before it says it’s focused but I’m still getting soft images. I did notice dust on the mirror. Would this cause my AF to mess up?


@MirandaH22 wrote:
The lens does move. I tried focusing in live view but it doesn’t help. I use back button focus normally. The lens searches for several seconds before it says it’s focused but I’m still getting soft images. I did notice dust on the mirror. Would this cause my AF to mess up?

It could if there's enough of it. But that wouldn't affect focusing in live view. The fact that neither focusing system works suggests that either the lens is defective or the sensor has become mispositioned. You said it's a used camera. One plausible guess is that it has been dropped.

Bob
Philadelphia, Pennsylvania USA

MirandaH22
Contributor
Ok I guess I should get it checked out. Idk why I’d just now be having problems with it though. I’ve used it every week since I bought it but the last 2 weeks is when it started acting up and I haven’t dropped either the lens or the camera


@MirandaH22 wrote:
Ok I guess I should get it checked out. Idk why I’d just now be having problems with it though. I’ve used it every week since I bought it but the last 2 weeks is when it started acting up and I haven’t dropped either the lens or the camera

I believe there have been two or three versions of the 50mm f/1.8, and I'm not familiar with any of them. But with some older Canon lenses, you can jam the autofocus motor if you try to focus the lens manually while it's set to autofocus mode. Conceivably that's what happened in your case. Sometimes the motor can be unjammed by brutally twisting the focus ring; the exact procedure has been described several times in the forum. It's a long shot, but it may be worth looking into.

Bob
Philadelphia, Pennsylvania USA


@RobertTheFat wrote:

@MirandaH22 wrote:
Ok I guess I should get it checked out. Idk why I’d just now be having problems with it though. I’ve used it every week since I bought it but the last 2 weeks is when it started acting up and I haven’t dropped either the lens or the camera

I believe there have been two or three versions of the 50mm f/1.8, and I'm not familiar with any of them. But with some older Canon lenses, you can jam the autofocus motor if you try to focus the lens manually while it's set to autofocus mode. Conceivably that's what happened in your case. Sometimes the motor can be unjammed by brutally twisting the focus ring; the exact procedure has been described several times in the forum. It's a long shot, but it may be worth looking into.


It is my understanding that when the AF motors have been forcibly misaligned, the AF motors can rattle when you shake the lens..

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MirandaH22
Contributor
Nothing is shaking. The lens is acting just like it did before this hardly focusing thing started. I’ve never manually focused either. It started acting up the first day of hot/humid weather. Humidity gets up to 80% or higher here in MS. Maybe I didn’t let it dry out enough? I never got any fog while outside or when I put it in the car but I have no idea what else it could be except just a random happening
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