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10D focus test 2 (skip this if you're not interested)
- Thread starter Pekka Saarinen
- Start date
I am a week away from ordering the following gear. Any input you might have would be greatly appreciated. I've been a Nikon user for 20+ years.
Some of the threads in these forums (this one in particular) makes me a bit concerned of my choice of Canon over Nikon because of all the poor focusing issues. Should this be a major concern? From the posts in this forum I'd be crazy to make this purchase. Is this the message I should take from this forum?
EOS 10D w/Battery Grip
Elan 7E w Battery Pack
Canon 24-70L
Canon 70-200 IS
550EX
(3) Extra BP511 Batteries
Off Camera Shoe Cord
2.0X Teleconverter
Dual Battery Charger
(3) Kingston 512 CF Cards
CF Reader (brand to be determined)
Tiffen 77mm Circ. Polarizer
Tiffen 77mm Soft Focus Filter
Kodak 8500 Printer
Rotatrim Pro 12" Trimmer
Stofen Omni Bounce for 550EX
Hoodma SLR Pro Shooter Kit
Thanks to all who comment and suggest.
Jeff
Some of the threads in these forums (this one in particular) makes me a bit concerned of my choice of Canon over Nikon because of all the poor focusing issues. Should this be a major concern? From the posts in this forum I'd be crazy to make this purchase. Is this the message I should take from this forum?
EOS 10D w/Battery Grip
Elan 7E w Battery Pack
Canon 24-70L
Canon 70-200 IS
550EX
(3) Extra BP511 Batteries
Off Camera Shoe Cord
2.0X Teleconverter
Dual Battery Charger
(3) Kingston 512 CF Cards
CF Reader (brand to be determined)
Tiffen 77mm Circ. Polarizer
Tiffen 77mm Soft Focus Filter
Kodak 8500 Printer
Rotatrim Pro 12" Trimmer
Stofen Omni Bounce for 550EX
Hoodma SLR Pro Shooter Kit
Thanks to all who comment and suggest.
Jeff
DavidP #28649
Forum Pro
I'd just move the target.
The main thing is keeping the AF sensor from picking up any lines other than the one that connects the upper and bottom parts of the chart, while keeping that line big enough to give good contrast.
The Unofficial Photographer of The Wilkinsons
http://thewilkinsons.crosswinds.net
Photography -- just another word for compromise
The main thing is keeping the AF sensor from picking up any lines other than the one that connects the upper and bottom parts of the chart, while keeping that line big enough to give good contrast.
--
The Unofficial Photographer of The Wilkinsons
http://thewilkinsons.crosswinds.net
Photography -- just another word for compromise
Pigasus
Leading Member
... from this discussion, is that when I buy my 10D, if I think it has focussing problems, I can test for it and if it appears not to be calibrated correctly, I can send it to Canon to be fixed. And while it may be a bit of a hassle getting an out of spec body repaired, I'll end up with a very well calibrated 10D.
Pigasus
The pig that flies
http://www.pigasusgrove.net/gallery/
--
Pigasus
The pig that flies
http://www.pigasusgrove.net/gallery/
FrancisCF
Leading Member
Not "if I think it has focussing problems...", is if I find out it has focussing problems in shooting, then you perform some test to verify it. You won't try to use a test to verify a good camera to be flawed.
Go ahead, never look back
--
Go ahead, never look back
Pekka Saarinen
Senior Member
This thread is about understanding issues that may arise when putting variety of lenses on a new body. 6 megapixels let you go deep down into the photo and see problems easily - I intend to print A3 size so that is why I pay attention to system calibration and try to find a way to analyze it and get it fixed.
I think it's great that we are finally finding a source for front/back focus and more importantly that it is not something "Canon just does". And I think that I made the right choice in gear because I hear this system CAN be calibrated.
One must see a difference between front/back focusing, focus fluctuation and misfocusing (note that I use "you" as passive):
- Front/back focusing is calibration problem and can be fixed by calibrating camera and lenses together. Reason for this maybe in lens, camera or both.
- Focus fluctuation means that focus point changes a little each time you focus. It is more likely to see this in low light. This varies from lens to lens and newer and L lenses have more accurate focusing motors. Of course lens calibration matters here too as if a lens is not in peak condition camera will not see perfectly though it either.
- Misfocusing is user error. AI servo for example needs you to read the manual, after you learn how it works it is very effective and accurate way to focus intelligently on moving subjects. One Shot focus needs you to find a little bit of contrast to make a lock. Overall you need to understand DoF and how plane of focus is related to camera angle. And you need to have enough shutter speed: the bigger you print the faster you have to go. 1/focal does not apply with cameras with 1.6X sensor. Add to that A3 print size and you'll see that to get really sharp images you need to crank up that speed much more than you expected.
10D as a camera is not "broken" in any way and I recommend it fully if you are looking for a camera in that price range. If I didn't like it I would not go though all this trouble. There are thousands of 10D's made and only some here and there may have slight miscalibration - it is only human that one sees posts about problems in bigger headings than posts "I like my 10D". In media war is always much more interesting than peace.
If you are worried about quality control ask them to check calibration between lenses and bodies you bought. After that is done you can be sure that your tools are not the weakest link. Please read message http://forums.dpreview.com/forums/read.asp?forum=1019&message=4927975
--
Pekka
http://photography-on-the.net
Whether it is flawed or not. I know the hot pixel metrics, I know the sharpness metrics, I know the AF metrics..whether the zoom lens is 1/3 -2/3 or even or other..all this takes about a day....and I have all of the data........to have confidence in the shooting....and have the data ....that establishes a baseline from day one.
The film mindset is do not do the tests -- just shoot.
The digital advantage is it allows us to know our calibration, our cams metrics for each lens...and then to maintain and have preventative maintenance performed on our cameras and lenses if need be.
Knowing.....is a good thing for me. Not knowing......is ok for others, but I think that such thought process is a film mindset.
If I send my gear in at some point...I'll know exactly how they adjusted the gear ... or have the data that they just ran it through the car wash.
Key Quality Principle of Crosby -- know your metrics.
MAC
MAC
http://www.digi-pictures.com
The film mindset is do not do the tests -- just shoot.
The digital advantage is it allows us to know our calibration, our cams metrics for each lens...and then to maintain and have preventative maintenance performed on our cameras and lenses if need be.
Knowing.....is a good thing for me. Not knowing......is ok for others, but I think that such thought process is a film mindset.
If I send my gear in at some point...I'll know exactly how they adjusted the gear ... or have the data that they just ran it through the car wash.
Key Quality Principle of Crosby -- know your metrics.
MAC
--
MAC
http://www.digi-pictures.com
Pigasus
Leading Member
Crumbs, Francis, that's what I meant. I would only think it had focussing problems if my real world results indicated so. Language is a tricky thing isn't it? ;-)
--
Pigasus
The pig that flies
http://www.pigasusgrove.net/gallery/
I started out a skeptic about the "focus problem" but the more I looked into my own lenses (a mix of Canon L and primes) the more I realized that there are some REAL problems and it may be more with the LENSES and how they are tested and spec'ed and NOT the 10D. This issue is compounded by the ability of users to accurately "test" their lenses with a high resolution digital camera. Basically we are using Lenses designed and spec’ed for film on a Digital camera.
Pekka is right that either the lens or the 10D can be at fault (or both), but unless you know which is causing the problem you could very well be blaming the wrong thing. My own experience and that of some others I have seen seems to suggest that it is the LENSES may be the source of MOST of the so-called "10D focusing problems."
Why do I suspect it is MOSTLY a lens problem:
1. I checked my lenses on a 10D and my 2 year old D30 an they both had very similar results. I very much doubt they were both miscalibrated the same way.
2. As Pekka says, with the 10D a lot of people are getting a camera that can show the problem. With Film, unless one is willing to test their lenses with rolls upon rolls of film and either scan it or blow up their pictures to large sizes, they would new KNOW if their lens was bad or they just mis-focused.
3. We have lenses that were designed and spec'ed for full frame 35mm Film. Yet we are using them on a 1.6X smaller format. This means that blur that is “acceptable” for a full frame print is not 1.6X too blurry. As I understand it (see topic below), and it makes sense from how an AF sensor works and from my testing are spec’ed with a 10D class of Auto Focus system to be focus within the Depth of Field at the lenses widest aperture (smallest F-number) using BUT this may be with a 35mm Sensor making a 5x7 print (or at most 8x10 print).
http://forums.dpreview.com/forums/read.asp?forum=1019&message=4460128
This causes 2 problems: First, with a 1.6X crop, being blown up to the same size print the tolerance has to be 1.6X smaller. But the LENSE can’t know this (it was designed a long time ago for full frame). Second, we are looking at output in Photoshop at 100% which is like looking at something like a 24x36 inch print at close range (way beyond a reasonable spec for lenses). Nobody can help people that have the second problem; these people have unrealistic expectations and would result in $10,000 for a 50F1.4 lens.
4. There is a “chasing your tail” problem built into the lens spec from 3) above and I think the implications of the “lens spec” may be bigger than some (many?) people realize. The fact that the “spec” is based on DoF with a .035 CoF which is pretty loose to begin with could be a major problem. Let’s say your lens is “just” within the spec. for 35mm film and say the DoF is 1 foot. But for a 10D the DoF would be only .625 feet and thus if the DoF just touched the 35mm DoF the point you focused on would be .375 feet out of the Depth of field. OK so now you either zoom out or back up so that you have a VERY large DoF (but still at the widest aperture) of the lens of say 20 Feet (DoF increases by the square of the size you make the subject at the focus point smaller). But because of the lens spec you subject is now 7.5 Feet out of the DoF. NO MATTER HOW FAR YOU ZOOM OUT or back up the subject will never be in focus at widest aperture.
5. So what can one do? First you can stop down. The focusing is spec’ed and done at widest aperture. The DoF will increase by the amount you stop down the F-number. Thus if you stop down by 1.6X (a little over 1 F-stop) you will bring the DoF back to were it was for 35mm film. But of course you have also lost 1 Stop of light and you have lost some of your DoF control. Second you have to get you lens calibrated to “better than the original spec” (assuming the posting from #3 above is right). It sounds like you can get the lens “tightened up.” Your lens technically was not bad as it was within the original tolerance, it just was not spec’ed as tight as you need it for a 10D (or it might be out of spec either when you bought it or after being used and bumped around for a while and you did not realize it before having a 10D to test it with).
For all these decades, amateurs had no way to realistically test their lenses. The “Pros” have sent their lenses in for calibration (any mechanical system will develop some slop). Sending something in for calibration is not something an “amateur” typical ever does.
6. Longer term is would be good if the AF sensor in digitals were more precise. It would be a lot easier to reduce the tolerance of the body rather than all of the lenses. Fixing the lenses is a mess as you have to have it work well over all zoom ranges and focus distances. If the 10D would focus within 1/3rd of the DoF range for 35mm film then most people would be very happy as this would mean that you would still allow for some slop with the lens. If the spec is 100% of the DoF then there are going to be a lot of people finding problems when both their Body and their Lenses are “within spec.”
You should note that I NEVER said that anybody was WRONG above. I am just trying to explain what I am seeing and that it agrees with what Pekka is seeing.
Pekka is right that either the lens or the 10D can be at fault (or both), but unless you know which is causing the problem you could very well be blaming the wrong thing. My own experience and that of some others I have seen seems to suggest that it is the LENSES may be the source of MOST of the so-called "10D focusing problems."
Why do I suspect it is MOSTLY a lens problem:
1. I checked my lenses on a 10D and my 2 year old D30 an they both had very similar results. I very much doubt they were both miscalibrated the same way.
2. As Pekka says, with the 10D a lot of people are getting a camera that can show the problem. With Film, unless one is willing to test their lenses with rolls upon rolls of film and either scan it or blow up their pictures to large sizes, they would new KNOW if their lens was bad or they just mis-focused.
3. We have lenses that were designed and spec'ed for full frame 35mm Film. Yet we are using them on a 1.6X smaller format. This means that blur that is “acceptable” for a full frame print is not 1.6X too blurry. As I understand it (see topic below), and it makes sense from how an AF sensor works and from my testing are spec’ed with a 10D class of Auto Focus system to be focus within the Depth of Field at the lenses widest aperture (smallest F-number) using BUT this may be with a 35mm Sensor making a 5x7 print (or at most 8x10 print).
http://forums.dpreview.com/forums/read.asp?forum=1019&message=4460128
This causes 2 problems: First, with a 1.6X crop, being blown up to the same size print the tolerance has to be 1.6X smaller. But the LENSE can’t know this (it was designed a long time ago for full frame). Second, we are looking at output in Photoshop at 100% which is like looking at something like a 24x36 inch print at close range (way beyond a reasonable spec for lenses). Nobody can help people that have the second problem; these people have unrealistic expectations and would result in $10,000 for a 50F1.4 lens.
4. There is a “chasing your tail” problem built into the lens spec from 3) above and I think the implications of the “lens spec” may be bigger than some (many?) people realize. The fact that the “spec” is based on DoF with a .035 CoF which is pretty loose to begin with could be a major problem. Let’s say your lens is “just” within the spec. for 35mm film and say the DoF is 1 foot. But for a 10D the DoF would be only .625 feet and thus if the DoF just touched the 35mm DoF the point you focused on would be .375 feet out of the Depth of field. OK so now you either zoom out or back up so that you have a VERY large DoF (but still at the widest aperture) of the lens of say 20 Feet (DoF increases by the square of the size you make the subject at the focus point smaller). But because of the lens spec you subject is now 7.5 Feet out of the DoF. NO MATTER HOW FAR YOU ZOOM OUT or back up the subject will never be in focus at widest aperture.
5. So what can one do? First you can stop down. The focusing is spec’ed and done at widest aperture. The DoF will increase by the amount you stop down the F-number. Thus if you stop down by 1.6X (a little over 1 F-stop) you will bring the DoF back to were it was for 35mm film. But of course you have also lost 1 Stop of light and you have lost some of your DoF control. Second you have to get you lens calibrated to “better than the original spec” (assuming the posting from #3 above is right). It sounds like you can get the lens “tightened up.” Your lens technically was not bad as it was within the original tolerance, it just was not spec’ed as tight as you need it for a 10D (or it might be out of spec either when you bought it or after being used and bumped around for a while and you did not realize it before having a 10D to test it with).
For all these decades, amateurs had no way to realistically test their lenses. The “Pros” have sent their lenses in for calibration (any mechanical system will develop some slop). Sending something in for calibration is not something an “amateur” typical ever does.
6. Longer term is would be good if the AF sensor in digitals were more precise. It would be a lot easier to reduce the tolerance of the body rather than all of the lenses. Fixing the lenses is a mess as you have to have it work well over all zoom ranges and focus distances. If the 10D would focus within 1/3rd of the DoF range for 35mm film then most people would be very happy as this would mean that you would still allow for some slop with the lens. If the spec is 100% of the DoF then there are going to be a lot of people finding problems when both their Body and their Lenses are “within spec.”
You should note that I NEVER said that anybody was WRONG above. I am just trying to explain what I am seeing and that it agrees with what Pekka is seeing.
bill jones
Leading Member
as the two previous posts mention there are many people who have perfectly working cameras and lenses
and the 10d is a great camera especially for the price.
also pointed out by many people on this forum is that certain lenses and certain cameras need to be calibrated. These problems do not seem like a rare enigma based on the number of posts we see here in this forum. To ME this indictaes canon has a quality control issues. I understand why there may be focus issues when using non-canon lenses. however, when we as consumers choose the canon eos system all lenses should be precisely
calibrated to the system as should all cameras. I understand as with any manufacuturing system there will always be lemons. there will aslo be units that get damaged in shipping. Canon with appropriate testing prior to shipping could determine if a particular lens or camera does not meet the standard. Reading these posts there a numerous examples of faulty lenses and camera. Take the post a few days ago where the user demonstarted through examples blury images from 24-70L went through two more lenses the thrid 24-70l was perfect. This is inexcusable. Why is it on this forum so many of you defend canon. Two post up the user states how great the Canon 10D is all you have to do is get your lens and camera calibrated.
We as consumers should expect to open up our boxes and find a perfectl compatible lens and camera. If canon had rigid testing standards this would be the case. If this only happend rarely the post on this forum would reflect by a lack of complaints. I am not whinning just scroll through the last 10 pages of posts and look how many people post about equipment problems related to QC its amazing. I wish the focus of this forum was techniques to improve the day to day use of slr canon cameras instead this forum should be renamed to " either my canon lens, camera body or flash don't seem to be working as promised" And for those of you who say quit complaining. It will be interesting to see how you respond when you too receive a faulty canon product. The quality of a company can be measured on its ability to deliver a product consistently without flaw to the consumer.
Are we forgetting the difficulty Canon had in delivering the D60 last year the entire yearthis camera was backordered why? Hugh demand. I don't think so. Do any of you actually think the demand for this camera is any higher than other models canon produces especially their point and shoot.
NO. Now they release the 10D which is widely available you can even buy it in best buy no significant backlog. How has canon acheived this miracle especially based on last years debacle.. I know they initiated a much tighter quality control program! If you are like me you work hard for your money don't settle for an inferior product "its ok that sometimes it doesn't focus" "just buy your lens at a store that takes returns sooner or later you will get a good one"
and the 10d is a great camera especially for the price.
also pointed out by many people on this forum is that certain lenses and certain cameras need to be calibrated. These problems do not seem like a rare enigma based on the number of posts we see here in this forum. To ME this indictaes canon has a quality control issues. I understand why there may be focus issues when using non-canon lenses. however, when we as consumers choose the canon eos system all lenses should be precisely
calibrated to the system as should all cameras. I understand as with any manufacuturing system there will always be lemons. there will aslo be units that get damaged in shipping. Canon with appropriate testing prior to shipping could determine if a particular lens or camera does not meet the standard. Reading these posts there a numerous examples of faulty lenses and camera. Take the post a few days ago where the user demonstarted through examples blury images from 24-70L went through two more lenses the thrid 24-70l was perfect. This is inexcusable. Why is it on this forum so many of you defend canon. Two post up the user states how great the Canon 10D is all you have to do is get your lens and camera calibrated.
We as consumers should expect to open up our boxes and find a perfectl compatible lens and camera. If canon had rigid testing standards this would be the case. If this only happend rarely the post on this forum would reflect by a lack of complaints. I am not whinning just scroll through the last 10 pages of posts and look how many people post about equipment problems related to QC its amazing. I wish the focus of this forum was techniques to improve the day to day use of slr canon cameras instead this forum should be renamed to " either my canon lens, camera body or flash don't seem to be working as promised" And for those of you who say quit complaining. It will be interesting to see how you respond when you too receive a faulty canon product. The quality of a company can be measured on its ability to deliver a product consistently without flaw to the consumer.
Are we forgetting the difficulty Canon had in delivering the D60 last year the entire yearthis camera was backordered why? Hugh demand. I don't think so. Do any of you actually think the demand for this camera is any higher than other models canon produces especially their point and shoot.
NO. Now they release the 10D which is widely available you can even buy it in best buy no significant backlog. How has canon acheived this miracle especially based on last years debacle.. I know they initiated a much tighter quality control program! If you are like me you work hard for your money don't settle for an inferior product "its ok that sometimes it doesn't focus" "just buy your lens at a store that takes returns sooner or later you will get a good one"
I think we may be victums of "unintendend consequences." I suspect that the "lenses" designed and used for 35mm film may be the biggest issue.
With the 1.6X crop factor driving a need for more sharpness and the easy ability to blow up any picture at will, we are seeing things now that were always there, but nobody bothered about before other than Pro's that tested their equipment and had it calibrated regularly.
All of a sudden, just about anybody can test their lenses to "Pro" standards.
There has to be some tollerance for every product. The tighter you make the tollerances the MORE EXPENSIVE it gets to maintain that tollerance.
Canon's spec in the "film days" may have been acceptable. But put that same lens on a 1.6X crop camera and it may not be acceptable. We have the added issue as to what tollerance the lens can hold with use. A lens that shipped within spec, may get a bit out of spec, but the Film shooter may not notice it at all. Same for the person using a F2.8 lens at F5.6 or F8, they will have no problem. But a Pro checking their lens or an Amateur with a 10D checking their lens at F2.8 start seeing all kinds of problems.
We have a mix of a lot of variables. The original tollerance and quality control. How things change with use. How people use and check their equipement. Peoples experience and testing methods. And the extra need for tighter specs with the 1.6X crop.
I am perfectly willing to believe that everything I bought was shipped within spec by Canon. But that does not mean that I, nor anyone else does not have a problem, particularly if they shoot at WIDE apertures.
With the 1.6X crop factor driving a need for more sharpness and the easy ability to blow up any picture at will, we are seeing things now that were always there, but nobody bothered about before other than Pro's that tested their equipment and had it calibrated regularly.
All of a sudden, just about anybody can test their lenses to "Pro" standards.
There has to be some tollerance for every product. The tighter you make the tollerances the MORE EXPENSIVE it gets to maintain that tollerance.
Canon's spec in the "film days" may have been acceptable. But put that same lens on a 1.6X crop camera and it may not be acceptable. We have the added issue as to what tollerance the lens can hold with use. A lens that shipped within spec, may get a bit out of spec, but the Film shooter may not notice it at all. Same for the person using a F2.8 lens at F5.6 or F8, they will have no problem. But a Pro checking their lens or an Amateur with a 10D checking their lens at F2.8 start seeing all kinds of problems.
We have a mix of a lot of variables. The original tollerance and quality control. How things change with use. How people use and check their equipement. Peoples experience and testing methods. And the extra need for tighter specs with the 1.6X crop.
I am perfectly willing to believe that everything I bought was shipped within spec by Canon. But that does not mean that I, nor anyone else does not have a problem, particularly if they shoot at WIDE apertures.
bill jones
Leading Member
Many good points especially taking inconsideration the 1.6 crop factor
it is interesting according to this forum, which is not the standard, there does seem to be a lot of issues with the 24-70L lens with people getting bad copies this is lens that would seem to be designed with digital cameras in mind.
it is interesting according to this forum, which is not the standard, there does seem to be a lot of issues with the 24-70L lens with people getting bad copies this is lens that would seem to be designed with digital cameras in mind.
Herman Dahlgren
Member
I have both an 1Ds and a 10D body and im having bad focusing problems 
Both bodys gives me almost identical results on my lenses, and all of my lenses are either front- or backfocusing. The only correctfocusing lense+body combination I have right now is my 10D and a 300/2.8L IS. My 1Ds body on the same lense gives me about 4-5 feet frontfocusing on a 100 feet distance.. that gives me quite blurry pictures because of the short DOF.
The 70-200@200mm tends to be approx. ½ feet behind on a 10 feet distance. =(
Im sending all my equipment to canon today. Hopefully it can all be calibrated.. otherwise it really STINKS.
It will probably cost some big bucks also =(
----------
1Ds, 10D
28-70/2.8L
70-200/2.8IS
300/2.8IS
85/1.2L
Both bodys gives me almost identical results on my lenses, and all of my lenses are either front- or backfocusing. The only correctfocusing lense+body combination I have right now is my 10D and a 300/2.8L IS. My 1Ds body on the same lense gives me about 4-5 feet frontfocusing on a 100 feet distance.. that gives me quite blurry pictures because of the short DOF.
The 70-200@200mm tends to be approx. ½ feet behind on a 10 feet distance. =(
Im sending all my equipment to canon today. Hopefully it can all be calibrated.. otherwise it really STINKS.
It will probably cost some big bucks also =(
----------
1Ds, 10D
28-70/2.8L
70-200/2.8IS
300/2.8IS
85/1.2L
This test is meaningless without the center box.
Why? Because it seems that you are aiming for the MIDDLE line and your boxes will touch the places that are in focus.
What i am saying is, if it focused on any point WITHIN the box, it's within spec and it seems like from most of your pic that's the case. You're shooting it at an angle, and as such, you will be covering from an odd angle plane anyway.
You can only make an argument it's an issue if you can show that it focused OUTSIDE the box. If it focused INSIDE the box, and it chooses to focused in the rear but still within the box, it's STILL a valid autofocus.
Tony
Gallery: http://violin.deviantart.com/gallery
Why? Because it seems that you are aiming for the MIDDLE line and your boxes will touch the places that are in focus.
What i am saying is, if it focused on any point WITHIN the box, it's within spec and it seems like from most of your pic that's the case. You're shooting it at an angle, and as such, you will be covering from an odd angle plane anyway.
You can only make an argument it's an issue if you can show that it focused OUTSIDE the box. If it focused INSIDE the box, and it chooses to focused in the rear but still within the box, it's STILL a valid autofocus.
Tony
--
Gallery: http://violin.deviantart.com/gallery
DavidP #28649
Forum Pro
The whole point of this particular test setup is to ensure that ONLY the one single vertical line is inside the AF "box" (area of the AF sensor).
This ensures there's only ONE place where the AF could possibly be trying to achieve focus.
The Unofficial Photographer of The Wilkinsons
http://thewilkinsons.crosswinds.net
Photography -- just another word for compromise
This ensures there's only ONE place where the AF could possibly be trying to achieve focus.
--
The Unofficial Photographer of The Wilkinsons
http://thewilkinsons.crosswinds.net
Photography -- just another word for compromise
Andrey Tverdokhleb
Well-known member
Actually in good light you can focus even on white paper.
In generall - all tests for autofocus made on angled target are wrong. The whole zone covered by focusing square must be near to parallel to you camera.
Andrey
In generall - all tests for autofocus made on angled target are wrong. The whole zone covered by focusing square must be near to parallel to you camera.
Andrey
DavidP #28649
Forum Pro
I suppose if the paper had enough texture on it, then perhaps it could be done.
FYI, Canon's own Service Manual has a chart that's held at an angle to the camera for adjusting and checking focus.
The Unofficial Photographer of The Wilkinsons
http://thewilkinsons.crosswinds.net
Photography -- just another word for compromise
FYI, Canon's own Service Manual has a chart that's held at an angle to the camera for adjusting and checking focus.
--
The Unofficial Photographer of The Wilkinsons
http://thewilkinsons.crosswinds.net
Photography -- just another word for compromise
Andrey Tverdokhleb
Well-known member
I didn't see their target. It's much simpler to make test on parallel target than on target at an angle, because in last case your target should be proprely designed for such tests and angle should be right too as per design (let me guess - 45 degrees for canon's?). The idea is to make sure that zone covered by focusing point is within DOF (at least).
Andrey
Andrey
MIB
Leading Member
I repeated exactly what you described on my 10D. The front/back focus is noticeable. The day time testing results are better than the ones performed during the night. Also, by making the center line thicker significantly improves the focus drifting.
Your testing results seem to be very seriously bad. Please keep us posted regarding the Canon service and how satisfied you are after the camera comes back.
regards,
'MIB'
Your testing results seem to be very seriously bad. Please keep us posted regarding the Canon service and how satisfied you are after the camera comes back.
regards,
--
'MIB'
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