Getting tired of getting Canon 24-70 2.8 L repaired

Should I go prime? Getting really tired of my Canon24-70 2.8 L (first generation). Have to send it back the 2nd time in 3 months for the same problem. Any person 15+ feet away are fuzzy, even though I had good focus lock, the person(s) are fuzzy, or anything of that matter while the background behind them are sharp. It worked for 2 months after the first repair and messing up again. First repair they said they had to change some rings and such. Surely they are not messed up again. Tried this lens on a 50D, 7D (where I did micro adjustment) and now a T5i, all the same problem. Shooting/focusing in live view did nothing to help - got focus lock but nothing along that plane is in focus - behind them are tack sharp. Even though my aperture is f/4 to f/8. Using a tripod up to 1/250, doesn't matter.

Anyone else having this problem with this lens? Did you find a solution?

It just sounds like they missed something during the first repair. Assuming it included a warranty, I'd let the same service give it another go. Did you send it to Canon or a local repair service?

according to Lensrentals.com (they did a tear down) - they have adjustment/sliding collars in there that wear out and cause softness... the mark II version is a much more robust build, and I'd suggest getting a mark II vs getting several primes if the cost is pretty close. JMHO. I don't have this lens for the variation in copy that I'd heard about for this reason. I'd buy the mark II if I had the money for it.

Agreed, I'm pretty sure their repairs include a pretty solid warrantee, I'd just send it back and say the problem is still occurring. I had to do that with my 17-55 when I had the zoom barrel replaced: two weeks later it was sticking at 35mm. Sent it back, and got it back sharper than its ever been and haven't had a problem since. I think when they have to do a repair for free because they screwed up the first one, there's extra incentive for them to get it really right...

Canon.

ksbal wrote in post #17919437
according to Lensrentals.com (they did a tear down) - they have adjustment/sliding collars in there that wear out and cause softness... the mark II version is a much more robust build, and I'd suggest getting a mark II vs getting several primes if the cost is pretty close. JMHO. I don't have this lens for the variation in copy that I'd heard about for this reason. I'd buy the mark II if I had the money for it.

I don't have the money for that. I had to charge this one at Best Buy a few years ago.

bseitz234 wrote in post #17919441
Agreed, I'm pretty sure their repairs include a pretty solid warrantee, I'd just send it back and say the problem is still occurring. I had to do that with my 17-55 when I had the zoom barrel replaced: two weeks later it was sticking at 35mm. Sent it back, and got it back sharper than its ever been and haven't had a problem since. I think when they have to do a repair for free because they screwed up the first one, there's extra incentive for them to get it really right...

Yeah, when canon repairs something it comes with a 6 month warranty on the same repair so I guess I will send it back this week and I hope you are right because it has been only a few months. I heard that every time I send it back for the same repair starts the 6 month warranty so at least I can send it back every 4 or 6 months if it keeps tearing up. It will be a very long time before I can afford the new one, will have to sell this one on ebay to get a prime or two.

I just read in a lot of other forums that many others have the same problem and the problem is when the lens is trying to focus on a low contrast point in less than perfect lighting, it will grab a high contrast point near what you are trying to focus on - that is why it is back focusing. I will try some testing on that tomorrow by putting a spotlight on someone's face so it will be contrasty and see if it grabs it in focus. I'll try that before sending it back. If that is what is happening I wonder if that can be fixed or is that the mechanical feature of the lens?

We'll see. I can't carry a spotlight with me everywhere I go, especially when doing a wedding so I may as well send it off.

Shooting wrote in post #17919809
I just read in a lot of other forums that many others have the same problem and the problem is when the lens is trying to focus on a low contrast point in less than perfect lighting, it will grab a high contrast point near what you are trying to focus on - that is why it is back focusing. I will try some testing on that tomorrow by putting a spotlight on someone's face so it will be contrasty and see if it grabs it in focus. I'll try that before sending it back. If that is what is happening I wonder if that can be fixed or is that the mechanical feature of the lens?

We'll see. I can't carry a spotlight with me everywhere I go, especially when doing a wedding so I may as well send it off.

The lens doesn't choose AF points. The *camera* will *always* focus on the highest-contrast edge that's in the area covered by your chosen AF point. Remember that the box you see in the viewfinder is NOT an exact match for the area that is covered, and you should test your camera to determine in which direction your display is offset. (There's the caveat of how you set up your AF options, which can result in nearby AF points being chosen, such as in area-AF, etc).

skid00skid00 wrote in post #17920073
The lens doesn't choose AF points. The *camera* will *always* focus on the highest-contrast edge that's in the area covered by your chosen AF point. Remember that the box you see in the viewfinder is NOT an exact match for the area that is covered, and you should test your camera to determine in which direction your display is offset. (There's the caveat of how you set up your AF options, which can result in nearby AF points being chosen, such as in area-AF, etc).

Ok. I always have the middle one and it is always back focusing when the people are 15+ feet away and I'm at 24mm. It worked 3 months ago when I got it back and now back to not working again.

So you are saying that maybe I should choose another focus point? Live view should work because it is spot focus, supposed to focus on whatever is in the focusing square, I do magnify up to 10 and it gives a green square when focused but it doesn't come out focused, live view is no help. Neither is zooming in, focusing and zooming out.

I have tried focusing on a face in the first row with one row behind them and yet it is the wall behind both walls that are in focus, I even moved the point down and focusing on a shirt with what I would consider a high contrast design and yet still it is the wall behind both rows of people that is in focus. If it is a single person I would try to focus on different things and yet it is what is behind them that is in focus. I'm at my wits end with this lens.

I dumped this lens a long time ago as it was not sharp wide open (well known issue).
First I replaced it with the Sigma 35 1.4 Art and later with the Tamron 24-70 2.8 VC.

The prime was nice for it's fastness & bokeh ability.
But I switched to the Tamron as it was almost as sharp as the Canon 24-70 2.8LII for a fraction of the price + it has VC + I had to do a wedding.
Normally I would have kept the prime, but I allready had the 50 Art also, so it was very close.

So it depends if you do lots of events/weddings I would buy the Tamron with no doubt, if no events/weddings the Sigma 35 Art.

Shooting wrote in post #17920647
Ok. I always have the middle one and it is always back focusing when the people are 15+ feet away and I'm at 24mm. It worked 3 months ago when I got it back and now back to not working again.

So you are saying that maybe I should choose another focus point? Live view should work because it is spot focus, supposed to focus on whatever is in the focusing square, I do magnify up to 10 and it gives a green square when focused but it doesn't come out focused, live view is no help. Neither is zooming in, focusing and zooming out.

I have tried focusing on a face in the first row with one row behind them and yet it is the wall behind both walls that are in focus, I even moved the point down and focusing on a shirt with what I would consider a high contrast design and yet still it is the wall behind both rows of people that is in focus. If it is a single person I would try to focus on different things and yet it is what is behind them that is in focus. I'm at my wits end with this lens.

If you are LV focusing at zoom 10, and you SEE that the image is sharp on the camera's LCD, but when you take the pic it isn't, then either:
A: focus changed before you tripped the shutter (are you immediately tripping the shutter on green box?)
B: the point you focused on was the only 'plane of focus' that's in-focus, and the rest of the subject is out of that plane (but this doesn't match your descr. of the wall behind being in-focus)

OTOH, if you are saying, above, that LV -with green square (indicating AF successful)- is NOT achieving focus, then flip the AF switch on the lens to 'ON'...
But seriously, I cannot imagine LV showing green if it didn't achieve focus. Send in the lens and camera.

Watch the lens' distance scale when you AF. Do you see it moving?

CanonYouCan wrote in post #17921968
I dumped this lens a long time ago as it was not sharp wide open (well known issue).
First I replaced it with the Sigma 35 1.4 Art and later with the Tamron 24-70 2.8 VC.

The prime was nice for it's fastness & bokeh ability.
But I switched to the Tamron as it was almost as sharp as the Canon 24-70 2.8LII for a fraction of the price + it has VC + I had to do a wedding.
Normally I would have kept the prime, but I allready had the 50 Art also, so it was very close.

So it depends if you do lots of events/weddings I would buy the Tamron with no doubt, if no events/weddings the Sigma 35 Art.

Well I sent it in this last time, if it still doesn't work right then it is going on ebay and I'll then try the Tamron. Weddings and events are about all I do, plus a headshot or two.

skid00skid00 wrote in post #17922004
If you are LV focusing at zoom 10, and you SEE that the image is sharp on the camera's LCD, but when you take the pic it isn't, then either:
A: focus changed before you tripped the shutter (are you immediately tripping the shutter on green box?)
B: the point you focused on was the only 'plane of focus' that's in-focus, and the rest of the subject is out of that plane (but this doesn't match your descr. of the wall behind being in-focus)

OTOH, if you are saying, above, that LV -with green square (indicating AF successful)- is NOT achieving focus, then flip the AF switch on the lens to 'ON'...
But seriously, I cannot imagine LV showing green if it didn't achieve focus. Send in the lens and camera.

Watch the lens' distance scale when you AF. Do you see it moving?

The green focusing square doesn't stay green very long. I read that you never take a picture with it still mag on 10, than you get the mag back to normal, by then the green square is gone and it is back to white, was that wrong? If that was wrong then no I did not shoot with the focusing on green. But it did look sharp on the lcd. I took a photo of my wife in a chair so nothing moved to change focusing plane and I had it on a tripod. I sent the lens in again but if it isn't fixed this time it is going on ebay. I did not send the camera in because it is not used on the same camera all the time. 2 weeks ago it was tested on a 50D and a 7D by another photographer with the very same results, back focusing with no recognizable face in the basketball team. Trouble is I'm still making payments on the thing.

I have used the ef 24-70mm f2.8 for years and years with no issues. It has been retired now with the purchase of version II.
That old guy did about a wedding a week so it's not like it set for any time. I used it on my 1Ds Mk III, great combo.