How To Get Your 450D AF Fixed

Started Apr 10, 2009 | Discussions
WilbaW
WilbaW Forum Pro • Posts: 11,642
How To Get Your 450D AF Fixed

When I became aware of discrepancies between the focus achieved by my 450D's phase detect and contrast detect autofocus modes, I verified that the the system was consistently not meeting Canon's specification. It was doing that with my 50/1.8 and 18-55 under certain conditions, e.g. near the minimum focal distance at wide apertures.

Here's one way I could show the error -

I called Canon in Sydney, they said fine, just send everything. I asked but the customer service guy wouldn't put me through to a technician or supervisor. I sent the camera body, my 50/1.8, 18-55, and 55-250, with a detailed explanation and a bunch of test shots on an SD card.

About four weeks later it came back with service notes like, "Extensively checked and tested, unit found to be working within manufacturer's specification. No fault found." The performance was the same as before, so I assume no adjustments were made.

When I called again, I was put through to a "customer consultant", who confessed he didn't have the technical knowledge to follow the story, but he was very willing to listen and help. I sent him the same files that went with the camera the first time, and after consulting with a "senior technician" he asked me to send in the camera again.

The consultant kept in touch with me throughout the four weeks the camera was away. He let me know when the technician confirmed that the system was not performing correctly.

Yesterday the camera came back. Now it does this -

The difference between the two methods is of the same order as the difference between shots using the same method. It doesn't get any better than that, and it seems to be spot on now with all of my lenses under all conditions.

The service notes say, "Best focusing has been performed, cleaned and tested all functions." So I don't know what has been adjusted or in what way.

The specific questions I asked, about the Canon specification and my camera's performance, were not answered, but they sent me some images of the focus achieved on their test rig. For instance, 50/1.8 @ f/4.5 -

So here are some observations. Canon Australia service staff are unfailingly polite and willing to help to the extent that their policies and procedures allow. They won't let you bug the technicians, and that's fair enough I guess.

When you send in a camera for "auto focus issues", it seems that a junior technician will test it against the specification, and may find that it passes those tests.

When you call to enquire about a warranty job that didn't fix your problem, you can get through to someone beyond the call centre. That person might not understand the technical issues, but they will consult with those who do, and will work with you to get it fixed.

The key seems to be to get past the first level of support. Others have reported that they weren't able to get a fix until they spoke to someone on the inside. The problem is, you will probably have to go through at least one cycle of sending the camera in before you can get to the second level.

Your camera will come back with everything reset to factory defaults, including any picture styles you have created. So before you send one in, make a note of your settings. My "My Menu" settings weren't affected.

My advice to anyone who thinks they have AF problems goes like this. Make sure you can repeatably show the problem as a difference between phase detect and contrast detect autofocus, under controlled conditions. Make sure that the difference puts the subject clearly outside the DOF at normal viewing sizes and distances. Use a wide aperture lens (f/2.8 or better if you can). Send your camera to Canon for calibration, but expect it to come back unchanged. Call Canon again, explain to the call centre guy that a warranty job didn't solve your problem, and ask to be put through to someone who can disuss it. Expect to be without your camera for many painful weeks, depending on how busy is your service centre.

For me, it was worth it.

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Canon EOS 60D Canon EOS 7D Mark II
Glenn_Sydney Senior Member • Posts: 1,449
Re: How To Get Your 450D AF Fixed

WilbaW wrote:

When I became aware of discrepancies between the focus achieved by my
450D's phase detect and contrast detect autofocus modes, I verified
that the the system was consistently not meeting Canon's
specification. It was doing that with my 50/1.8 and 18-55 under
certain conditions, e.g. near the minimum focal distance at wide
apertures.

Here's one way I could show the error -

I called Canon in Sydney, they said fine, just send everything. I
asked but the customer service guy wouldn't put me through to a
technician or supervisor. I sent the camera body, my 50/1.8, 18-55,
and 55-250, with a detailed explanation and a bunch of test shots on
an SD card.

About four weeks later it came back with service notes like,
"Extensively checked and tested, unit found to be working within
manufacturer's specification. No fault found." The performance was
the same as before, so I assume no adjustments were made.

When I called again, I was put through to a "customer consultant",
who confessed he didn't have the technical knowledge to follow the
story, but he was very willing to listen and help. I sent him the
same files that went with the camera the first time, and after
consulting with a "senior technician" he asked me to send in the
camera again.

The consultant kept in touch with me throughout the four weeks the
camera was away. He let me know when the technician confirmed that
the system was not performing correctly.

Yesterday the camera came back. Now it does this -

The difference between the two methods is of the same order as the
difference between shots using the same method. It doesn't get any
better than that, and it seems to be spot on now with all of my
lenses under all conditions.

The service notes say, "Best focusing has been performed, cleaned and
tested all functions." So I don't know what has been adjusted or in
what way.

The specific questions I asked, about the Canon specification and my
camera's performance, were not answered, but they sent me some images
of the focus achieved on their test rig. For instance, 50/1.8 @ f/4.5
-

So here are some observations. Canon Australia service staff are
unfailingly polite and willing to help to the extent that their
policies and procedures allow. They won't let you bug the
technicians, and that's fair enough I guess.

When you send in a camera for "auto focus issues", it seems that a
junior technician will test it against the specification, and may
find that it passes those tests.

When you call to enquire about a warranty job that didn't fix your
problem, you can get through to someone beyond the call centre. That
person might not understand the technical issues, but they will
consult with those who do, and will work with you to get it fixed.

The key seems to be to get past the first level of support. Others
have reported that they weren't able to get a fix until they spoke to
someone on the inside. The problem is, you will probably have to go
through at least one cycle of sending the camera in before you can
get to the second level.

Your camera will come back with everything reset to factory defaults,
including any picture styles you have created. So before you send one
in, make a note of your settings. My "My Menu" settings weren't
affected.

My advice to anyone who thinks they have AF problems goes like this.
Make sure you can repeatably show the problem as a difference between
phase detect and contrast detect autofocus, under controlled
conditions. Make sure that the difference puts the subject clearly
outside the DOF at normal viewing sizes and distances. Use a wide
aperture lens (f/2.8 or better if you can). Send your camera to Canon
for calibration, but expect it to come back unchanged. Call Canon
again, explain to the call centre guy that a warranty job didn't
solve your problem, and ask to be put through to someone who can
disuss it. Expect to be without your camera for many painful weeks,
depending on how busy is your service centre.

For me, it was worth it.

-- hide signature --

Thanks for taking the time to put together an elaborate explanation. Good job in getting it fixed. By the way, what is Canons specification for auto focus and what does it deem as "acceptable" ? Is this documented on the web site or where can one find it ?

WilbaW
OP WilbaW Forum Pro • Posts: 11,642
Re: How To Get Your 450D AF Fixed

Glenn_Sydney wrote:

Thanks for taking the time to put together an elaborate explanation.
Good job in getting it fixed.

No worries, thanks.

By the way, what is Canons specification for auto focus and what does it
deem as "acceptable" ?
Is this documented on the web site or where can one find it ?

I wish it was available as such. That was one of the questions I asked - just what is the spec.?

They sent me a couple of photocopied pages from a book, but there is no title or reference. I get the impression that it is a Canon document about the basics of photography.

It says, "For 35mm single lens reflex cameras, the permissible circle of confusion is about 1/1000~1/1500 the length of the film diagonal, assuming the image is enlarged to a 5"x7" (12 cm x 16.5 cm) print and viewed from a distance of 25~30cm/0.8~1 ft. EF lenses are designed to produce a minimum circle of confusion of 0.035 mm, a value on which calculations for items such as depth of field are based."

That suggests a COC for a Rebel sensor of 0.027-0.018mm, which agrees with 0.035/1.6mm.

A 5x7" print at 1ft is a pretty slack standard. The classic 0.03mm COC for a print viewed at a distance equivalent to its diagonal, is a tougher mark to reach.

The other thing that's widely understood and quoted is that an AF sensor like the centre point in a Rebel should put the subject within the DOF for lenses worse than f/2.8, and within 1/3 of the DOF with f/2.8 or better.

Put it this way, if you display an image on your monitor at "best fit" size (the full image filling the screen), view it from a distance something like the screen size or greater, and the subject is clearly not within the DOF, you have a focus error on that shot.

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Canon EOS 60D Canon EOS 7D Mark II
Glenn_Sydney Senior Member • Posts: 1,449
Re: How To Get Your 450D AF Fixed

WilbaW wrote:

Put it this way, if you display an image on your monitor at "best
fit" size (the full image filling the screen), view it from a
distance something like the screen size or greater, and the subject
is clearly not within the DOF, you have a focus error on that shot.

-- hide signature --

Thanks for the explanation. I guess when you say "......and the subject

is clearly not within the DOF", you mean the subject is clearly blurry ?

AnthonyL Veteran Member • Posts: 3,642
Re: How To Get Your 450D AF Fixed

WilbaW wrote:

The key seems to be to get past the first level of support. Others
have reported that they weren't able to get a fix until they spoke to
someone on the inside. The problem is, you will probably have to go
through at least one cycle of sending the camera in before you can
get to the second level.

That really should not be necessary if they subsequently find something to fix.

For me, it was worth it.

I can see it would be a relief. Glad your camera is working and thankful mine appears to not have any issues.

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Canon EOS 700D Canon EF-S 10-22mm F3.5-4.5 USM Canon EF-S 55-250mm f/4-5.6 IS Canon EF 40mm f/2.8 STM Canon EF-S 18-55mm f/3.5-5.6 IS STM +5 more
Gary Hunt Senior Member • Posts: 1,058
Re: How To Get Your 450D AF Fixed

Unfortunately I had to go through the same procedures in the UK with regards to a UX issue.

You are correct in saying that they will not allow you to speak to a technician if you ask but in the end they did phone me & I was able to talk to the top dog.

My issue was solved after I stopped listening to all the user error insults I received here & sent the camera in along with loads of test shots & test shots using another canon DSLR to compare with. The technician phoned me & confirmed that the camera's metering was 1 stop under & it was fixed at last using some new calibration software as they did for many others who had the same problem.

You know if you have a AF problem or not regardless of the doubters here so you need to keep sending it back until you get a fix & insist you speak to the top guy/girl. These cameras are entry level DSLRs & should focus spot on most of the time unless you are seriously making big mistakes & Canon need to sort out there testing of these cameras because from what I see they are not getting it right.

spur Regular Member • Posts: 208
Re: How To Get Your 450D AF Fixed

I had much the same experience with Canon in the US.
http://forums.dpreview.com/forums/read.asp?forum=1031&message=29966110

It's a fun camera when it is working right. I wish all the "experts" around here that think everything is user error would have to take all of their shots with a camera that front focuse all the time.

Oxheart Contributing Member • Posts: 876
Re: How To Get Your 450D AF Fixed

Nice post and useful as well.

Here's the service note I got back from Canon on the lens I sent in & received back yesterday:

I still don't think it's quite right, but need to do more testing to see what's really going on.

ETA: mine was an 18-55 IS kit lens, purchased with the camera in late January (almost new).

jsmiller Contributing Member • Posts: 826
Re: How To Get Your 450D AF Fixed. How familiar it all sounds!

WilbaW wrote:

The key seems to be to get past the first level of support. Others
have reported that they weren't able to get a fix until they spoke to
someone on the inside. The problem is, you will probably have to go
through at least one cycle of sending the camera in before you can
get to the second level.

Your experience almost identically mirrors mine, except it took me three tries here in the US before I reached a high enough level to get the right person to listen. On the second and third tries I did talk directly to some technicians, but their knowledge was sadly lacking. One said I could cure my problem by always stopping down my lens to f/8 or f/11. The final, critical person, as near as I can tell, was a Senior Service Supervisor, and we discussed the issues and cameras in general at length. Thought he was on the East Coast and I sent my camera to a California repair center, he followed the repair personally. In my case I really don't know what they did, but as with your camera, mine now does focus reliably the same in the two modes. ...Except for the latest new Sigma lens I just bought- front focus again. But I'm attempting to adjust the focus on that myself. I don't want to send the camera and lens in again and be without it for a month. If people are interested, I'll post my results, be they success or disaster. I'll know today.

Joe

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Canon PowerShot ELPH 360 HS
Oxheart Contributing Member • Posts: 876
Yes, please Joe

Joe, please post your results. I'd like to know the outcome.

WilbaW
OP WilbaW Forum Pro • Posts: 11,642
Re: How To Get Your 450D AF Fixed

Glenn_Sydney wrote:

WilbaW wrote:

Put it this way, if you display an image on your monitor at "best
fit" size (the full image filling the screen), view it from a
distance something like the screen size or greater, and the subject
is clearly not within the DOF, you have a focus error on that shot.

Thanks for the explanation. I guess when you say "......and the subject
is clearly not within the DOF", you mean the subject is clearly blurry ?

Yeah. Check the phase detect image in the before comparison -

The lens focussed at f/1.8, and it should have put "Focus here" within the inner 1/3 of the DOF. The shot was taken at f/2.8, which gives a DOF about 1.6 times deeper than f/1.8, and the subject is not within that DOF by my judgement. See how the plane of sharp focus is at about the 4mm mark?

These animated GIFs are about the same size on my screen as the original images displayed at "best fit". That's about a 340mm diagonal, and I can see that the subject is not in the DOF from 1m away (but then I have very sharp eyesight).

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Canon EOS 60D Canon EOS 7D Mark II
WilbaW
OP WilbaW Forum Pro • Posts: 11,642
Re: How To Get Your 450D AF Fixed

AnthonyL wrote:

WilbaW wrote:

The key seems to be to get past the first level of support. Others
have reported that they weren't able to get a fix until they spoke to
someone on the inside. The problem is, you will probably have to go
through at least one cycle of sending the camera in before you can
get to the second level.

That really should not be necessary if they subsequently find
something to fix.

I can understand it. In my experience, the customer service departments of large businesses have levels of support and kinda triage processes, and you kinda have to work your way through to the higher levels.

For me, it was worth it.

I can see it would be a relief. Glad your camera is working and
thankful mine appears to not have any issues.

Thanks, yeah, congrats on getting a good one.

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Canon EOS 60D Canon EOS 7D Mark II
WilbaW
OP WilbaW Forum Pro • Posts: 11,642
Re: How To Get Your 450D AF Fixed

Gary Hunt wrote:

Unfortunately I had to go through the same procedures in the UK with
regards to a UX issue.

You are correct in saying that they will not allow you to speak to a
technician if you ask but in the end they did phone me & I was able
to talk to the top dog.

One of the reasons I particularly wanted to talk to the senior technician was to find out what they use to make the adjustment. The call centre guy was able to tell me that they do it "via software" (OMG!), but I wanted to know if it was one function of a large application, or a little applet ... that could be "accidentally" left on a customer's SD card ...

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Canon EOS 60D Canon EOS 7D Mark II
WilbaW
OP WilbaW Forum Pro • Posts: 11,642
Re: How To Get Your 450D AF Fixed

spur wrote:

I had much the same experience with Canon in the US.
http://forums.dpreview.com/forums/read.asp?forum=1031&message=29966110

It's a fun camera when it is working right. I wish all the "experts"
around here that think everything is user error would have to take
all of their shots with a camera that front focuse all the time.

The funniest ones are those that quote someone elses writing about AF, as if it explains away your problem as the result of ignorance, and the quoted material is useful in proving that the camera isn't working properly.

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Canon EOS 60D Canon EOS 7D Mark II
WilbaW
OP WilbaW Forum Pro • Posts: 11,642
Re: How To Get Your 450D AF Fixed

Oxheart wrote:

Nice post and useful as well.

Thanks. I hope that knowledge might save someone else from some grief. Don't give up!

Here's the service note I got back from Canon on the lens I sent in &
received back yesterday:
[image snipped]
I still don't think it's quite right, but need to do more testing to
see what's really going on.

ETA: mine was an 18-55 IS kit lens, purchased with the camera in late
January (almost new).

Good luck with that.

To avoid having to send my camera and lenses away for a month every time I buy a new one, I'll be buying new lenses from shops where I can test a few units on site and take the best.

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Canon EOS 60D Canon EOS 7D Mark II
WilbaW
OP WilbaW Forum Pro • Posts: 11,642
Re: How To Get Your 450D AF Fixed. How familiar it all sounds!

jsmiller wrote:

WilbaW wrote:

The key seems to be to get past the first level of support. Others
have reported that they weren't able to get a fix until they spoke to
someone on the inside. The problem is, you will probably have to go
through at least one cycle of sending the camera in before you can
get to the second level.

Your experience almost identically mirrors mine, except it took me
three tries here in the US before I reached a high enough level to
get the right person to listen. On the second and third tries I did
talk directly to some technicians, but their knowledge was sadly
lacking. One said I could cure my problem by always stopping down my
lens to f/8 or f/11. The final, critical person, as near as I can
tell, was a Senior Service Supervisor, and we discussed the issues
and cameras in general at length. Thought he was on the East Coast
and I sent my camera to a California repair center, he followed the
repair personally. In my case I really don't know what they did, but
as with your camera, mine now does focus reliably the same in the two
modes. ...Except for the latest new Sigma lens I just bought- front
focus again. But I'm attempting to adjust the focus on that myself. I
don't want to send the camera and lens in again and be without it for
a month. If people are interested, I'll post my results, be they
success or disaster. I'll know today.

Yeah, I'd like to know how it came out. You would adjust the Sigma with shims behind the mount?

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Canon EOS 60D Canon EOS 7D Mark II
Oxheart Contributing Member • Posts: 876
Re: How To Get Your 450D AF Fixed

WilbaW wrote:

Oxheart wrote:

Nice post and useful as well.

Thanks. I hope that knowledge might save someone else from some
grief. Don't give up!

Here's the service note I got back from Canon on the lens I sent in &
received back yesterday:
[image snipped]
I still don't think it's quite right, but need to do more testing to
see what's really going on.

ETA: mine was an 18-55 IS kit lens, purchased with the camera in late
January (almost new).

Good luck with that.

To avoid having to send my camera and lenses away for a month every
time I buy a new one, I'll be buying new lenses from shops where I
can test a few units on site and take the best.

That makes sense. I am in a very rural area (in the Rocky Mountains) or I'd do the same... Closest Canon dealer of any size is 200 miles S.

I'm looking hard at my options for upgrading to a different body in the Canon lineup or to a different brand. I really want AF micro adjust on my next camera.

WilbaW
OP WilbaW Forum Pro • Posts: 11,642
Re: How To Get Your 450D AF Fixed - Update

I asked the consultant how people could avoid having to send in their cameras more than once to get them fixed. He suggested sending images and a detailed description with the camera.

I explained that that's exactly what I did. He suspects that the problem was with the way the camera was booked in. For the original repair job, their system just says "auto focus issues" - none of the images or words I sent with the camera got onto the system. The technicians only go on what's on the system, so they never saw the evidence the first time around.

So maybe the trick is to get your evidence onto the system that the technicians use to track jobs. Maybe we need to e-mail that in and wait for them to request the camera. Or put your evidence on a memory card, tape it to the outside of the camera, with something like, "Technician - please read the document on this card!!" written on it.

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Canon EOS 60D Canon EOS 7D Mark II
Sulac0 Regular Member • Posts: 283
Re: How To Get Your 450D AF Fixed - Update

You guys are all going through the same thing we all went through back when the original digital Rebel (300D) first hit the market. A lot of folks then (myself included) all had front and back focusing issues. We all sent in test shots on focus charts, test images, documentation, etc., etc.

The only thing Canon would do is adjust the body to within what they considered acceptable focusing specifications and then adjust any lenses we sent it with the body to properly focus (or as close as possible) with the particular body. You can see the problem with this. What about other lenses? So yeah, needless to say, the problem seems to be with the entry level dSLR's and the specs are just too broad on the 1.6x crop bodies in my opinion.

I gave my 300D to my dad (can't see anyway) and when I replace it, I will go up a level or two.

PeaceFrog Forum Pro • Posts: 12,185
Re: How To Get Your 450D AF Fixed - Update

I sure do remember the howling around here back when the 10D came out. It seemed like lots of people were struggling with Canon to get their cameras adjusted only to get them back still performing poorly along with a note saying that the camera has been adjusted to meet spec…

It isn’t just the entry level SLR’s.

Greg

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