Canon - hunting for focus

Dolby

Dolby

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Anyone had an issue with lens hunting for focus?

I have a 7D and 17-55 which has worked for years, but just taken it out now and it hunts for focus. That's green, auto focus, reset every setting etc

I noticed that if I'm zoomed out (17mm) it seems to latch on - but zooming into anything and it hunts.

No other lens here to see if lens or body.

Any idea?
 
Dolby said:
How is Canon repairs regarding costs?
Click to expand...
Cameratek - Expensive and crap. Each time they've repaired my lens I've had to send it back due to soft focusing.

Orms in CPT are taking over canon [warranty] repairs from Cameratek so they might be worth a shot if that's your neighbourhood.
 
Thanks bwana - I'll mail them ... but I'm in Johannesburg unfortunately.

Judging by the link, there's a definitely something that needs to be replaced. Not soft - but no locking on at all
 
I vaguely remember a piece of Canon software that shows green blocks on the PC screen of those parts in focus.

Anyone know offhand what it was ?
 
I gave 2 of my cameras in for service/repairs to an independent (former Canon employee). Will get them back today and then hand over another two. Will report back and maybe he is good enough to use instead of Cameratek, if you want?
 
Dolby said:
I vaguely remember a piece of Canon software that shows green blocks on the PC screen of those parts in focus.

Anyone know offhand what it was ?
Click to expand...

DPP will show you the FPs that you used but it won't necessarily mean it's in focus.

Screen Shot 2016-06-28 at 2016•06•28 11.04.25 .jpg

EDIT: as you can see in the picture the image is clearly out of focus and this was after Cameratek returned the camera.
 
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If you want to have it inspected/repaired, give Sunray Photographic Services in Linden, JHB a call...speak to Steven...don't have the contact details handy now but google will pick it up - he has an excellent reputation, I have personal experience with him, he is one of the best.
 
Thanks guys!

Yea I've heard from others to avoid Cameratek
 
If you're having focusing problems it's best to send the your camera and the lens so they can calibrate them both effectively.
 
The EF-S 17-55mm f/2.8 IS USM, EF-S 17-85mm f/4-5.6 IS USM, EF 24-105mm f/4L IS USM and a few other lenses all share a common design flaw which sees their aperture module's flex cable pinch, crack and begin shorting. Though that cable serves to control NOTHING but the aperture, for all three the lenses listed and the variety of others affected by the same issue the first symptom the user will encounter when it begins to fail is always focus hunting when 'zoomed in'.

Some lenses, like the EF-S 17-85 (eighty-five) can be safely taken apart by the user to replace the entire aperture+cable assembly or to replace the cable alone; others like the EF 24-105mm will need to be recalibrated thereafter making it a non-user-servicable part. I can't remember whether it's 'safe' to do the repair oneself on the EF-S 17-55 (fifty-five) as it's been too long since I was last reading up about the issue.

And yes, CameraTek are the South African repair agents appointed by Samsung, and sat with my camera for two months only to return it and the lens I needed them to work on having done nothing but give the camera body a blowjob to deal with its one control dial skipping (there was dust in there), not doing anything about my other issues. They also seem to love not responding to mails until harassed about the things...
 
So Cameratek were convenient and dropped the lens off there. If I get it back and still not working, I'll get it couriered to Orms. Their quote is so vague that I'm not sure it'll be

camera.jpg



@ nanonyous - doesn't like that, because it can't focus at all - but the lens that I posted about also happens to be a 17-55mm ... so maybe you're right?
 
nanonyous said:
The EF-S 17-55mm f/2.8 IS USM, EF-S 17-85mm f/4-5.6 IS USM, EF 24-105mm f/4L IS USM and a few other lenses all share a common design flaw which sees their aperture module's flex cable pinch, crack and begin shorting. Though that cable serves to control NOTHING but the aperture, for all three the lenses listed and the variety of others affected by the same issue the first symptom the user will encounter when it begins to fail is always focus hunting when 'zoomed in'.

Some lenses, like the EF-S 17-85 (eighty-five) can be safely taken apart by the user to replace the entire aperture+cable assembly or to replace the cable alone; others like the EF 24-105mm will need to be recalibrated thereafter making it a non-user-servicable part. I can't remember whether it's 'safe' to do the repair oneself on the EF-S 17-55 (fifty-five) as it's been too long since I was last reading up about the issue.
Click to expand...

Agree with you.I had the same problem with the EF-S 17-85 lens. Orms replaced the flex ribbon cable and all was sorted.

IMG_A18143_600.jpg
 
absynth said:
Agree with you.I had the same problem with the EF-S 17-85 lens. Orms replaced the flex ribbon cable and all was sorted
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Same symptoms as mine ?
How much was it?

This guy describes it quite well, because 17mm is no issue ... but as I move out, it is :

https://www.dpreview.com/forums/post/37989071

Is the EXIF information on focal length recorded in the file correct? If your camera cannot get this information from the lens, then it cannot tell the lens precisely how far to move the AF. The lens would hunt because it is still out of focus. At the long end, the DOF is more shallow and you see it more often.

I had this problem last month. I described this symptom to Canon. They overlooked the focal length reporting problem. They just replaced the AF motor. The problem remained. I have to call to make another arrangement to send it in again. This time, they replace the focal length sensing brush. Now it works.
 
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Dolby said:
Same symptoms as mine ?
How much was it?

This guy describes it quite well, because 17mm is no issue ... but as I move out, it is :
Click to expand...

If I remember correctly at 17mm it was fine,but when you use zoom(I think when the ribbon cable starts moving the break in it would not make contact) then it would not focus.

They replaced only the cable and not the whole assembly if memory serves me well and it was about R1500.Maybe about 3 years ago.

Also Orms technicians are good.Fixed that lens for me,did sensor work on my Canon 50d,both pieces of equipment received back and you wouldn't even say that it was disassembled.
 
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Thanks - same symptoms.

They just phoned me and gave a totally difference reason for my lens breaking - they said they don't need to replace anything and it's all labour to fix the zoom unit etc. Eventually, I said I'll give the benefit as he opened the lens and before I take it, I'll double and triple check.

He said if I'm unhappy, he'll repair at their own cost
 
Dolby said:
Thanks - same symptoms.

They just phoned me and gave a totally difference reason for my lens breaking - they said they don't need to replace anything and it's all labour to fix the zoom unit etc. Eventually, I said I'll give the benefit as he opened the lens and before I take it, I'll double and triple check.

He said if I'm unhappy, he'll repair at their own cost
Click to expand...

Hope you get it sorted.
 
I've seen more than a few people solidly slating Cameratek in another forum. I've used them a few times for minor jobs, not what I would call professional service.
 
Got my lens back yesterday (R1,640) and well, it worked.

No one can really explain what the issue was other than 'zoom unit' - although when they were explaining, it did sound like the ribbon cable mentioned above. I must be honest, they weren't too bad with me .. but the 3 month guarantee on workmanship is a bit disappointing.

Seems sharp as well

https://postimg.org/image/rgaktvvpr/
 
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