20D focusing....

Started Mar 21, 2005 | Discussions
Eden Yip Senior Member • Posts: 2,059
20D focusing....

want to know how do you guys feel about the accuracy of the 20D focusing.

went thro the hassles of exchanging/recal the 70-200/4. canon tech once adjusted my 20D focus to compensate for the issues with 70-200/4, which i disliked cuz it would make me not possible to use 3rd party and other canon lens, e.g. the famous looked soft with my 20D. canon has lately restored my 20D focus to the defaults.

tried again the camera with the lenses and reviewed some of the old test photos.. i am going to believe the focus issue is with my 20D. (canon tech believed it as well but they thought it was becuz of the dirty pins at the mount). the 50/1.8 exhibited softness at aperture faster than F2.8. i thought it is normal but after reviewing the photos from my sold D70 and 50/1.8D which is sharp at F2.0.

Test photos from 50/1.8 with tripod and AF assist on, the focus was about hit and miss and looked more consistent beyond F5.0. test photos from 70-200/4 in real life has shown the focus is inaccurate (even under good sunlight) with relatively lower constrast targets, e.g. far shots of faces, flowers (with patterns), adv. sign board with red fonts on blue background, etc. the focus offset is quite significant.

I know the focus would work the best when targetting on high constrast objects but i havn't thought the 20D focus could be that worse. surely my D70 with sigma 70-300 APO focus noticably accurate under daylight. the 70-200/4 however can get the focus right when under good lighting on highly contrast targets (black text on orange, blue text on white and even the neon light sign board at dark!!)

my question is .. is the 20D that inaccuracy and only work rite on highly contrast objects?

pls share with me some ideas...

cuz of the focus issues i have been hestiated to buy fast lens, e.g. 85/1.8...

Wild-Mike
Wild-Mike Veteran Member • Posts: 5,910
Re: 20D focusing....

Eden Yip wrote:

my question is .. is the 20D that inaccuracy and only work rite on
highly contrast objects?

pls share with me some ideas...

cuz of the focus issues i have been hestiated to buy fast lens,
e.g. 85/1.8...

I don't have any problems with the 85mm f/1.8 lens or any of the other lenses I own. I shoot wide open too and still no problems with focus.

Regards,
Mike

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New Gallery (in development stage) http://wnyphoto.com
Photography is just one of my hobbies

ARShutterbug
ARShutterbug Veteran Member • Posts: 8,925
Re: 20D focusing....

Do you see the image as being out of focus before the picture is taken?

Kathy Malaspina Forum Member • Posts: 57
Re: 20D focusing....

Lock your focus in on the center spot in the circle. Its so sharp it could cut you......

ARShutterbug wrote:

Do you see the image as being out of focus before the picture is
taken?

ARShutterbug
ARShutterbug Veteran Member • Posts: 8,925
Re: 20D focusing....

Lock your focus in on the center spot in the circle. Its so sharp
it could cut you......

I have been seeing lots of OOF problems after pictures are taken. The image is sharp in the viewfinder, but blurry at the focus point afterward. The part that's in focus in the picture is nowhere close, and the problem is not camera shake. It's like the AF system is focusing on something else after the shutter button is depressed. I complain when I get 10 similarly bad pictures in a row, and when a day of shooting returns more than 25% OOF pictures. Even a different 20D body with a 17-40 lens had the problem. The first picture was good, but the next was blurry at the selected focus point. I tried focusing on a bookshelf in low-light and the AF system appeared to be working correctly. When the problem occurs, the image is clearly in focus at the focus point when the shutter button is depressed halfway, but it's blurry at that point after the shutter release. The problem is not continuous, but it seems to increase when shooting high-contrast subjects. I can try going to MF to see what happens, but the problem doesn't seem to happen at any particular time. I'm just glad that the camera hasn't had this OOF problem when capturing any rare images for which you only get that one shot.

Kathy Malaspina Forum Member • Posts: 57
Re: 20D focusing....

ARShutterbug wrote:

Do you see the image as being out of focus before the picture is
taken?

Change the focas settings. First set the cameras on anything from P to M.
Cannot change setting on the Green square-

On the back of the camera, the button that enlarges the photo.....upper right corner.
Push the button and then dial the large wheel on the back of the camera.
You will see the red dots start to move in the view finder.
Dial it until ONLY the center red dot is set.

You have now reset your focus-It will no longer be bouncing all over the place, focusing on everything in the viewfinder.

No more back focusing, etc. Hey I bought 2-20D's last week, I was pretty upset, the focusing sucked. Emailed Canon, they just gave me the this advice.
1. There is no problem with the focusing on the 20D's--Big LIE
2. The images should be viewed from a distance--)LOL-yea Right)

3. You may be experiencing camera shake, and gave me instructions on how to hold the camera...(PLEASE--I am a professional with 18 years experience shooting with equipment that weighs a ton, with camera, flash, strobotone,stroboframe grip,long lenses, off camera flash modules, and battery cords hooked to power packs etc.} I think I can hold a camera. I can hold it perfectly at 30 shutter.....
4.Use your photo editing software to sharpen your images.....
5.The images will look much better once you print them....

Good grief, I was laughing......How about let us tell you how to get rid of our 9 point focusing system

That would have been the thing they should have told me.....but I read and figured it out.

I also own Nikons and the Kodak Pro/SLR/N---the Canon is now as sharp as those.

Good Luck.

mwj Regular Member • Posts: 340
Re: 20D focusing....

Eden Yip wrote:

Test photos from 50/1.8 with tripod and AF assist on, the focus was
about hit and miss and looked more consistent beyond F5.0. test
photos from 70-200/4 in real life has shown the focus is inaccurate
(even under good sunlight) with relatively lower constrast targets,
e.g. far shots of faces, flowers (with patterns), adv. sign board
with red fonts on blue background, etc. the focus offset is quite
significant.

I've gone through two 20d's, both of which had this problem. The dealer couldn't find one in stock that didn't have this problem and Canon can't find one for them either - they said send it in to be fixed. I can't see paying full retail + shipping charges to have a camera refurbished when I could buy a refurbished camera and save hundreds of dollars, so I'm just getting a refund. With all this I've rather lost my zeal for photography, so I think I'll stick with my P&S for a while and use the money elsewhere.

My advice is to return the camera for exchange/refund if you can. If not, send it in and hope Canon thinks you're important enough to fix your camera - there have been many reports of Canon just sending them back and saying "it's within spec".

Good luck.

mwj

Eden Yip OP Senior Member • Posts: 2,059
Re: 20D focusing....

sorrie not really get you. do u mean to set to the center focus pt at M mode?

what was your foucsing problem? was it only with lower contrast objects?

Kathy Malaspina wrote:

ARShutterbug wrote:

Do you see the image as being out of focus before the picture is
taken?

Change the focas settings. First set the cameras on anything from
P to M.
Cannot change setting on the Green square-
On the back of the camera, the button that enlarges the
photo.....upper right corner.
Push the button and then dial the large wheel on the back of the
camera.
You will see the red dots start to move in the view finder.
Dial it until ONLY the center red dot is set.
You have now reset your focus-It will no longer be bouncing all
over the place, focusing on everything in the viewfinder.
No more back focusing, etc. Hey I bought 2-20D's last week, I was
pretty upset, the focusing sucked. Emailed Canon, they just gave me
the this advice.
1. There is no problem with the focusing on the 20D's--Big LIE
2. The images should be viewed from a distance--)LOL-yea Right)
3. You may be experiencing camera shake, and gave me instructions
on how to hold the camera...(PLEASE--I am a professional with 18
years experience shooting with equipment that weighs a ton, with
camera, flash, strobotone,stroboframe grip,long lenses, off camera
flash modules, and battery cords hooked to power packs etc.} I
think I can hold a camera. I can hold it perfectly at 30
shutter.....
4.Use your photo editing software to sharpen your images.....
5.The images will look much better once you print them....

Good grief, I was laughing......How about let us tell you how to
get rid of our 9 point focusing system
That would have been the thing they should have told me.....but I
read and figured it out.

I also own Nikons and the Kodak Pro/SLR/N---the Canon is now as
sharp as those.

Good Luck.

Grant Y Senior Member • Posts: 1,120
Re: 20D focusing....

fixed. I can't see paying full retail + shipping charges to have a
camera refurbished when I could buy a refurbished camera and save
hundreds of dollars, so I'm just getting a refund.

It's called "adjustment" or "calibration" (presuming it is something other than cockpit error). That doesn't constitute a refurb. I have a lab full of electronic test equipment that makes the price of a 20D look like round-off error. I pay a calibration lab to go through the equipment every 12 months. None of it is "refurbished".

If you thought you had a hardware issue with the camera or lens you should have just sent it to Canon. This business of swapping out 3 or 4 of everything at the camera counter is about as non-productive an approach as I can imagine -- more or less equivalent to self-flagellation, particularly since there are a large percentage of guys behind the counter that know less than you do. All it would have cost is the price of shipping to a Canon service facility (since this stuff is covered under warranty, and Canon pays return shipping).

The longest wait I've had for two items sent to Canon is 10 calendar days, door-to-door. A small price to pay .... but then I must now be using a refurbished 20D since I had Canon recalibrate the flash exposure system

-- hide signature --

Grant

If it's TRUTH you're after ..
.. read the multiplication table.

Kathy Malaspina Forum Member • Posts: 57
Re: 20D focusing....

Eden Yip wrote:

sorrie not really get you. do u mean to set to the center focus pt

at M mode? I did it step by step for you. You can set it at every mode exceptFull Auto-which is the green square.

what was your foucsing problem? was it only with lower contrast

objects? Everything was soft and the fous points were all over the place. It didn't matter what it was.

I guess most people that are here are amateurs, and they only use Full Auto. Thats the problem, and why there are so many complaints.

There is nothing wrong with the 20D once you set it right.

Canon told me in their email basically the same thing. That they cannot control what amateurs who buy this camera say on forums. More that it is the operator, not the equipment. Thats why they were talking to me like a 2 year old, about how to hold the camera, etc....

I hope you figure out what I wrote this time about setting it.

Good luck,

Kathy Malaspina wrote:

ARShutterbug wrote:

Do you see the image as being out of focus before the picture is
taken?

Change the focas settings. First set the cameras on anything from
P to M.
Cannot change setting on the Green square-
On the back of the camera, the button that enlarges the
photo.....upper right corner.
Push the button and then dial the large wheel on the back of the
camera.
You will see the red dots start to move in the view finder.
Dial it until ONLY the center red dot is set.
You have now reset your focus-It will no longer be bouncing all
over the place, focusing on everything in the viewfinder.
No more back focusing, etc. Hey I bought 2-20D's last week, I was
pretty upset, the focusing sucked. Emailed Canon, they just gave me
the this advice.
1. There is no problem with the focusing on the 20D's--Big LIE
2. The images should be viewed from a distance--)LOL-yea Right)
3. You may be experiencing camera shake, and gave me instructions
on how to hold the camera...(PLEASE--I am a professional with 18
years experience shooting with equipment that weighs a ton, with
camera, flash, strobotone,stroboframe grip,long lenses, off camera
flash modules, and battery cords hooked to power packs etc.} I
think I can hold a camera. I can hold it perfectly at 30
shutter.....
4.Use your photo editing software to sharpen your images.....
5.The images will look much better once you print them....

Good grief, I was laughing......How about let us tell you how to
get rid of our 9 point focusing system
That would have been the thing they should have told me.....but I
read and figured it out.

I also own Nikons and the Kodak Pro/SLR/N---the Canon is now as
sharp as those.

Good Luck.

mwj Regular Member • Posts: 340
Re: 20D focusing....

Grant Y wrote:

fixed. I can't see paying full retail + shipping charges to have a
camera refurbished when I could buy a refurbished camera and save
hundreds of dollars, so I'm just getting a refund.

It's called "adjustment" or "calibration" (presuming it is
something other than cockpit error). That doesn't constitute a
refurb.

The camera store agreed that once it is sent to Canon it is no longer returnable.

As for it being an adjustment, I'm sure you're right in 95% of the cases. I'm just not willing to risk CDN$3000 (camera & lens) on a 5% gamble. Search this list - there are numerous reports where Canon either sends it back unchanged or even worse.

If you thought you had a hardware issue with the camera or lens you
should have just sent it to Canon.

I asked Canon whether if I dropped by could they take a look at it and tell me if it needs calibration. They said No. They can take it in for repair only.

All it
would have cost is the price of shipping to a Canon service
facility (since this stuff is covered under warranty, and Canon
pays return shipping).

It's a $2000 dollar camera. Why should it have to be shipped in to be fixed right out of the box. That's ridiculous. For that money it should work.

A small price to pay .... but then I
must now be using a refurbished 20D since I had Canon recalibrate
the flash exposure system

Yup. You just saved Canon hundreds of dollars in refurbished cameras. I hope they at least sent you a Thank You card.

mwj

Eden Yip OP Senior Member • Posts: 2,059
Re: 20D focusing....

i thought you told some secret trick that at manual metering the focus would be accurate as expected. :>

yes, many amateus here but doesn't imply they should use full auto. i wonder any amatuer here would buy a US$1500 20D to use it in full auto mode.

as said by some other members someone who have not own a camera/lens with focus issues would not be able to understand how itching/frustrating it can be....

i will try to post some shots here to illustrate the issues.

Kathy Malaspina wrote:

Eden Yip wrote:

sorrie not really get you. do u mean to set to the center focus pt

at M mode? I did it step by step for you. You can set it at every mode exceptFull Auto-which is the green square.

what was your foucsing problem? was it only with lower contrast

objects? Everything was soft and the fous points were all over the place. It didn't matter what it was.

I guess most people that are here are amateurs, and they only use
Full Auto. Thats the problem, and why there are so many complaints.

There is nothing wrong with the 20D once you set it right.

Canon told me in their email basically the same thing. That they
cannot control what amateurs who buy this camera say on forums.
More that it is the operator, not the equipment. Thats why they
were talking to me like a 2 year old, about how to hold the camera,
etc....

I hope you figure out what I wrote this time about setting it.

Good luck,

Kathy Malaspina wrote:

ARShutterbug wrote:

Do you see the image as being out of focus before the picture is
taken?

Change the focas settings. First set the cameras on anything from
P to M.
Cannot change setting on the Green square-
On the back of the camera, the button that enlarges the
photo.....upper right corner.
Push the button and then dial the large wheel on the back of the
camera.
You will see the red dots start to move in the view finder.
Dial it until ONLY the center red dot is set.
You have now reset your focus-It will no longer be bouncing all
over the place, focusing on everything in the viewfinder.
No more back focusing, etc. Hey I bought 2-20D's last week, I was
pretty upset, the focusing sucked. Emailed Canon, they just gave me
the this advice.
1. There is no problem with the focusing on the 20D's--Big LIE
2. The images should be viewed from a distance--)LOL-yea Right)
3. You may be experiencing camera shake, and gave me instructions
on how to hold the camera...(PLEASE--I am a professional with 18
years experience shooting with equipment that weighs a ton, with
camera, flash, strobotone,stroboframe grip,long lenses, off camera
flash modules, and battery cords hooked to power packs etc.} I
think I can hold a camera. I can hold it perfectly at 30
shutter.....
4.Use your photo editing software to sharpen your images.....
5.The images will look much better once you print them....

Good grief, I was laughing......How about let us tell you how to
get rid of our 9 point focusing system
That would have been the thing they should have told me.....but I
read and figured it out.

I also own Nikons and the Kodak Pro/SLR/N---the Canon is now as
sharp as those.

Good Luck.

RDKirk Forum Pro • Posts: 14,786
Re: 20D focusing....

mwj wrote:

It's a $2000 dollar camera. Why should it have to be shipped in to
be fixed right out of the box. That's ridiculous. For that money
it should work.

Actually, the more versatile and precise it is, the more likely it is to need calibration. Target pistols have to calibrated (sighted in)...sawed-off shotguns do not.

There are two ways Canon can do this. They can add $100 USD to every camera to tweak them individually at the factory, or they can offer to do it for free as after-purchase service. Is the second method really inferior, considering that most cameras don't really need it?

-- hide signature --

RDKirk
'TANSTAAFL: The only unbreakable rule in photography.'

 RDKirk's gear list:RDKirk's gear list
Canon EOS 5D Mark II Canon EOS 70D Canon EF 24mm f/2.8 Canon EF 85mm f/1.8 USM Canon EF-S 17-55mm f/2.8 IS USM +5 more
RDKirk Forum Pro • Posts: 14,786
Take these steps...

1. First shoot some photos in good light of contrasty subjects using manual focus. Be sure your shutter speed is 1/500 or faster. Check the images for sharpness at 25% on the computer or on an A5 print, NOT on the camera LCD.

If the manually focused images are sharp, go to step 2. If they are not sharp the camera is misaligned and needs servicing.

2. Shoot some photos with the autofocus in good light with contrasty subjects. As you shoot, be sure to notice specifically whether or not the camera focuses on what you intend. There are techniques involved in using autofocus correctly, and these take practice and observation to learn. For instance, the area seen by the autofocus system is actually much larger than the markings, so the camera may focus on something just outside the markings if it has stronger contrast. So check to be sure the camera is focusing in the viewscreen on what you want. If the camera is focusing on the viewscreen on the right subject, check for sharpness on the monitor at 25% or on an A5 print.

If the autofocused images are sharp, all is well. If they are not sharp, you will need to send the camera or lens to the serivice center for calibration. Canon may want to calibrate both of them (they are separately calibrated against standard test equipment--they are NOT matched to each other). If it's a non-Canon lens, send it to its manufacturer for calibration. Include the blurry prints.

-- hide signature --

RDKirk
'TANSTAAFL: The only unbreakable rule in photography.'

 RDKirk's gear list:RDKirk's gear list
Canon EOS 5D Mark II Canon EOS 70D Canon EF 24mm f/2.8 Canon EF 85mm f/1.8 USM Canon EF-S 17-55mm f/2.8 IS USM +5 more
Eden Yip OP Senior Member • Posts: 2,059
Re: 20D focusing....

for your second approach. i think it is logically incorrect and sounds like assuming responsibilties of falut checking by the end users. with quality committtment to customers, canon shall verify, not 100% not sampling at a confident level, the camera/any product are with standards out of the factory.

RDKirk wrote:

There are two ways Canon can do this. They can add $100 USD to
every camera to tweak them individually at the factory, or they can
offer to do it for free as after-purchase service. Is the second
method really inferior, considering that most cameras don't really
need it?

-- hide signature --

RDKirk
'TANSTAAFL: The only unbreakable rule in photography.'

Eden Yip OP Senior Member • Posts: 2,059
Re: Take these steps...

what do u mean by contrast objects. or, should the 20D only work well for highly constrast objects?

the canon tech first said the focus inaccuracy, as more noticable with my 50/1.8 at fast apertures, was with the bad motor. he replaced the motor. Then said the 20D pins were dirty and cause the focus issues.

my recal 70-200/4 now works ok for highly contrast objects, e.g. adv boards with black text on orange or green text on white, etc. but not ok for red on blue, yellow on green, flowers, far shots of ppl faces, etc. in real life and to catch the moment, it is not easy to find as such highly contrast objects nearby the targets. and all in all, the focus accuracy (not the speed) of 20D is noticably inaccurate than D70/sigma. which may not work dead on the focus, but the offset is not that much....

my 50/1.8 now works strangely. the focus is hit and miss and the variations is noticable when faster than F4. i am not sure it is the problem with the lens again. if it is not the problem with the camera, it would be too unlucky to have two bad lens.

RDKirk wrote:

1. First shoot some photos in good light of contrasty subjects
using manual focus. Be sure your shutter speed is 1/500 or faster.
Check the images for sharpness at 25% on the computer or on an A5
print, NOT on the camera LCD.

If the manually focused images are sharp, go to step 2. If they
are not sharp the camera is misaligned and needs servicing.

2. Shoot some photos with the autofocus in good light with
contrasty subjects. As you shoot, be sure to notice specifically
whether or not the camera focuses on what you intend. There are
techniques involved in using autofocus correctly, and these take
practice and observation to learn. For instance, the area seen by
the autofocus system is actually much larger than the markings, so
the camera may focus on something just outside the markings if it
has stronger contrast. So check to be sure the camera is focusing
in the viewscreen on what you want. If the camera is focusing on
the viewscreen on the right subject, check for sharpness on the
monitor at 25% or on an A5 print.

If the autofocused images are sharp, all is well. If they are not
sharp, you will need to send the camera or lens to the serivice
center for calibration. Canon may want to calibrate both of them
(they are separately calibrated against standard test
equipment--they are NOT matched to each other). If it's a
non-Canon lens, send it to its manufacturer for calibration.
Include the blurry prints.

-- hide signature --

RDKirk
'TANSTAAFL: The only unbreakable rule in photography.'

Hoang Pham Contributing Member • Posts: 686
focusing is perfect

Eden Yip wrote:
for your second approach. i think it is logically incorrect and
sounds like assuming responsibilties of falut checking by the end
users. with quality committtment to customers, canon shall verify,
not 100% not sampling at a confident level, the camera/any product
are with standards out of the factory.

RDKirk wrote:

There are two ways Canon can do this. They can add $100 USD to
every camera to tweak them individually at the factory, or they can
offer to do it for free as after-purchase service. Is the second
method really inferior, considering that most cameras don't really
need it?

-- hide signature --

RDKirk
'TANSTAAFL: The only unbreakable rule in photography.'

-- hide signature --
jedoaks Regular Member • Posts: 279
Kathy, wow , I hope you are right

I took your advice and changed the focus point to the center. Now my Sig 18-50 seems to be spot on. I was going to send the lens back to Sig.I'll try it out tomorrow. I never did like the focus area . Thanks, rich

Kathy Malaspina wrote:

ARShutterbug wrote:

Do you see the image as being out of focus before the picture is
taken?

Change the focas settings. First set the cameras on anything from
P to M.
Cannot change setting on the Green square-
On the back of the camera, the button that enlarges the
photo.....upper right corner.
Push the button and then dial the large wheel on the back of the
camera.
You will see the red dots start to move in the view finder.
Dial it until ONLY the center red dot is set.
You have now reset your focus-It will no longer be bouncing all
over the place, focusing on everything in the viewfinder.
No more back focusing, etc. Hey I bought 2-20D's last week, I was
pretty upset, the focusing sucked. Emailed Canon, they just gave me
the this advice.
1. There is no problem with the focusing on the 20D's--Big LIE
2. The images should be viewed from a distance--)LOL-yea Right)
3. You may be experiencing camera shake, and gave me instructions
on how to hold the camera...(PLEASE--I am a professional with 18
years experience shooting with equipment that weighs a ton, with
camera, flash, strobotone,stroboframe grip,long lenses, off camera
flash modules, and battery cords hooked to power packs etc.} I
think I can hold a camera. I can hold it perfectly at 30
shutter.....
4.Use your photo editing software to sharpen your images.....
5.The images will look much better once you print them....

Good grief, I was laughing......How about let us tell you how to
get rid of our 9 point focusing system
That would have been the thing they should have told me.....but I
read and figured it out.

I also own Nikons and the Kodak Pro/SLR/N---the Canon is now as
sharp as those.

Good Luck.

AK_2 Senior Member • Posts: 1,019
Use a 2 piece chart, and expect 'hit or miss' . . . .

Some describe focus as hit or miss - assuming your technique is correct, to say focus is hit or miss is surprisingly 100% correct. But, before anyone flames me, let me point out what 'hit or miss' might mean.

Let's say hit means 100% perfect focus, lets say miss is not 100% perfect focus - in thats sense the camera will almost always miss

BUT - it doesn't need to be 100% perfect to give a great sharp shot.

Within 1x dof is a reasonable resutl for sharpness, within 1/3rd dof gives a stunningly sharp brilliant shot. Every single canon dslr from 10d to 1dmk2 varies with each shot in the same situation with regard focus.

A good 1dmk2 vaires with typically half the dof. A 10d typically varies within 3x dof.

The 20d is a little unusual. It has a consumer af sensor in the middle, and a higher precision sensor (but not the same as a pro body).

Each sensor is geared for different apertures in an ideal world.

The precision sensor works best with f2.8 lenses of modern desgin, like the new 70-200isL2.8 or 24-70f2.8L, and very well with the Sigma 28-702.8.

The 20d with a 50mm 1.4 is dreadful, the 85mm 1.8 just within 1x dof, the 70-200f4 just within dof.

http://www.canon-dslr.com - focus test page, at end of page, download focus chart pieces.

You can test for yourself using this 2 piece chart with perpendicular focus target and angled measure rule grid. Test at x40 or x50 focal length (e.g. 50mm is 2m-2.5m, 200mm is 8m-10m), 4500-6500k, 6-12ev, tripod, cable release, focus once each time with one shot, and do 4 SHOTS, 2 from nearest focus and 2 from infiitny focus - you'll be shocked at the results.

You'll see two things - a big varience per shot (the tolerance of the system, which explains the hit or miss for many, especially with a poorly suited lens), and then when you average the mean of the 4 shots, you can see the overall accuracy. YOU WILL LIKELY FIND overall accuracy to end up with the 20d across a range of lenses to be within half dof. But the varience (or tolerance) might see some shots, notably with 50mm 1.4 only within 2x dof.

Regards,
kev

mwj Regular Member • Posts: 340
Re: 20D focusing....

RDKirk wrote:

mwj wrote:

It's a $2000 dollar camera. Why should it have to be shipped in to
be fixed right out of the box. That's ridiculous. For that money
it should work.

Actually, the more versatile and precise it is, the more likely it
is to need calibration. Target pistols have to calibrated (sighted
in)...sawed-off shotguns do not.

There are two ways Canon can do this. They can add $100 USD to
every camera to tweak them individually at the factory, or they can
offer to do it for free as after-purchase service. Is the second
method really inferior, considering that most cameras don't really
need it?

So what about people who buy a 20d with the kit lens or 17-85? They may not even notice a problem until their warranty expires and they go to buy a 2.8 or faster lens as their skills increase. Will Canon still adjust their camera for free?

Anyways, I doubt it would cost Canon $100 per camera to have a robot that puts a lens on a camera, takes a picture, then checks it for sharpness.

mwj

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